Igniter

Abstract

The igniter comprises a metal shell and a circuit board assembly, a charging interface is fixed to one end of the circuit board assembly, and a heating wire assembly is fixed to the other end of the circuit board assembly; a battery is arranged on the circuit board assembly, the charging interface is used for charging the battery, and the battery is used for supplying power to the heating wire assembly; the device further comprises an insulating base plate. The metal shell comprises an upper shell body and a lower shell body, and the upper shell body and the lower shell body are respectively an integrated piece. The upper shell and the lower shell are detachably matched, and after the upper shell and the lower shell are matched, a mounting space for accommodating the circuit board assembly is formed; a fire making hole is formed in the upper shell, and the heating wire assembly is located in the fire making hole. The lower shell comprises a bottom plate, and a first electricity taking hole is formed in the bottom plate; the insulating base plate comprises a body part, a second electricity taking hole is formed in the body part, the size of the second electricity taking hole is smaller than that of the first electricity taking hole, and the second electricity taking hole corresponds to the first electricity taking hole; the end, provided with the charging interface, of the circuit board assembly abuts against the body part, and the charging interface penetrates through the second electricity taking hole and then is exposed in the first electricity taking hole. The cable has the advantage of being good in insulation performance.

Description

Technical Field

[0001] The present application relates to an igniter. Background Art

[0002] In ancient times, the igniter was also called a fire stick. The user would unscrew the cover and blow gently. This was achieved by using flammable materials such as straw paper, sulfur, and phosphorus.

[0003] In modern society, there is an electronic ignition device, also called a cigarette lighter, which uses a battery to heat a resistor to achieve the purpose of ignition.

[0004] In order to make this electronic igniter usable repeatedly, a rechargeable battery, a USB interface, and a charging management circuit are often used to enable the battery to be repeatedly charged, thereby ensuring that the igniter can be reused.

[0005] However, there are two main options for the shell of the existing electronic igniter, one is pure metal material, and the other is a two-layer shell structure (the inner layer is metal, and the outer layer is insulating material). For the pure metal structure, if the insulation design between the USB interface and the metal shell is unreasonable, there may be safety risks.

[0006] Therefore, it is necessary to design an igniter with relatively good insulation performance. Summary of the invention

[0007] In view of this, the purpose of this application is to overcome the deficiencies in the prior art and to provide an igniter.

[0008] The present application provides: an igniter, which includes a metal shell and a circuit board assembly, a charging interface is fixed at one end of the circuit board assembly, and a heating wire assembly is fixed at the other end of the circuit board assembly; a battery is arranged on the circuit board assembly, the charging interface is used to charge the battery, and the battery is used to supply power to the heating wire assembly; wherein, an insulating pad is also included; the metal shell includes an upper shell and a lower shell, and the upper shell and the lower shell are each an integral part; the upper shell and the lower shell are detachably matched, and the two are matched to form an installation space for accommodating the circuit board assembly; a fire hole is provided on the upper shell, and the heating wire assembly is located in the fire hole; the lower shell includes a bottom plate, and a first power hole is provided on the bottom plate; the insulating pad includes a main body, a second power hole is provided on the main body, the size of the second power hole is smaller than the size of the first power hole, and the second power hole corresponds to the first power hole; one end of the circuit board assembly having a charging interface is abutted against the main body, and the charging interface is exposed in the first power hole after passing through the second power hole.

[0009] By adopting this structure and the design of the insulating pad, the charging port and the base plate are not in direct contact, the insulation performance can be improved as much as possible, and the design of this structure is also very convenient, requiring only the circuit board assembly to be against the insulating pad.

[0010] In some embodiments of the present application, an annular protrusion is provided on the insulating pad, and the annular protrusion surrounds the second power extraction hole; the annular protrusion is located between the hole wall of the first power extraction hole and the side of the charging interface.

[0011] This structure and the design of the annular protrusion further improve the insulation performance between the charging interface and the bottom plate. At the same time, the annular protrusion is located between the hole wall of the first power extraction hole and the side of the charging interface, which can also play a certain limiting effect, ensuring that the circuit board assembly passes through the charging interface and forms a limit between the bottom plate.

[0012] In some embodiments of the present application, a limiting groove is provided on the upper shell at the ignition hole, and a matching protrusion is provided on the heating wire assembly, and the matching protrusion extends into the limiting groove to form a limiting fit.

[0013] By adopting this structure, the limiting of the matching protrusion and the limiting groove, combined with the limiting formed between the annular protrusion and the bottom plate, a stable limiting structure can be formed between the circuit board assembly and the metal shell. This limiting structure has the characteristics of easy assembly and reliable limiting.

[0014] In some embodiments of the present application, the lower shell includes a lower side wall surrounding the bottom plate, the lower side wall is connected to the bottom plate to form a first inner cavity, and the first inner cavity is part of the installation space; the first inner cavity has an upper opening, and the upper opening has an orthographic projection area S1 on the bottom plate, and the circuit board assembly has an orthographic projection area S2 on the bottom plate, and S1 is greater than S2.

[0015] By adopting this structure and the structural design of the lower shell and ensuring that S1 is greater than S2, contact between the circuit board assembly and the lower side wall can be avoided as much as possible, further improving the insulation performance.

[0016] In some embodiments of the present application, the circuit board assembly includes a circuit board substrate, and the circuit board substrate is not in direct contact with the metal housing.

[0017] With this structure, the circuit board substrate does not directly contact the metal shell, which further improves the insulation performance.

[0018] In some embodiments of the present application, the metal shell is in a three-dimensional gourd shape.

[0019] By adopting this structure, the three-dimensional gourd-shaped structure can not only ensure the beautiful appearance of the product, but also have a large enough space to accommodate electronic components.

[0020] In some embodiments of the present application, the charging interface is a USB interface; or / and, one of the upper shell and the lower shell is provided with an internal thread, and the other is provided with an external thread, and the internal thread and the external thread cooperate to form a detachable fit between the upper shell and the lower shell.

[0021] The USB interface can adapt to most adapters on the market. The threaded connection ensures that the upper and lower shells are easy to disassemble and assemble.

[0022] In some embodiments of the present application, a plug is also included, which is removably matched with the fire hole and is used to close the fire hole.

[0023] In some embodiments of the present application, the battery is welded to the circuit board assembly.

[0024] Soldering the battery directly onto the circuit board assembly can make the battery and the circuit board assembly form a whole, which will be beneficial to the assembly of the battery and the circuit board assembly.

[0025] In some embodiments of the present application, the circuit board assembly includes a charging management circuit, a single-chip microcomputer, an air pressure sensing circuit and a MOS tube; the charging interface is electrically connected to the charging management circuit, the charging management circuit is electrically connected to the single-chip microcomputer and the battery, and the charging interface charges the battery through the charging management circuit; the battery is electrically connected to the single-chip microcomputer and one end of the heating wire assembly, and is used to power the single-chip microcomputer and the heating wire assembly; the air pressure sensing circuit is electrically connected to the single-chip microcomputer, and converts the external air pressure into an electrical signal and feeds it back to the single-chip microcomputer; the single-chip microcomputer is connected to the gate of the MOS tube, the drain of the MOS tube is grounded, the drain of the MOS tube is connected to the other end of the heating wire assembly, and the source of the MOS tube is grounded; the single-chip microcomputer turns on the MOS tube according to the electrical signal converted by the air pressure sensing circuit to heat the heating wire assembly; the air pressure sensing element of the air pressure sensing circuit is arranged close to the heating wire assembly and is connected to the gap on the heating wire assembly.

[0026] With this structure, the air pressure sensing element is set near the heating wire assembly, and the air pressure sensing circuit is used to convert the user's "blowing action" into an electrical signal. The MOS tube is then controlled to be turned on through a single-chip microcomputer, which can easily achieve the "blowing to ignite" effect, simulating the use of ancient fire sticks.

[0027] In some embodiments of the present application, the air pressure sensing circuit includes a microphone, a transistor Q1, a capacitor C2, a resistor R3 and a resistor R4; the microphone is an air pressure sensing element, the negative pole of the microphone is grounded, the positive pole of the microphone is coupled with the B pole of the transistor Q1 through the capacitor C2, and the resistor R3 is electrically connected between the positive pole of the microphone and a pin of the single-chip microcomputer; the C pole of the transistor Q1 is electrically connected to a pin of the single-chip microcomputer, the E pole of the transistor Q1 is grounded, and the resistor R4 is electrically connected between the B pole of the transistor Q1 and the E pole of the transistor Q1.

[0028] By adopting this structure, a simple circuit can be used to convert the user's "blowing action" into an electrical signal, and the structure is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 An exploded view of the igniter of Example 1 of the present application is shown;

[0031] Figure 2 A three-dimensional diagram of the igniter of Example 1 of the present application is shown;

[0032] Figure 3 A schematic diagram showing the cooperation between the circuit board assembly and the insulating pad in the igniter of Example 1 of the present application is shown;

[0033] Figure 4 A cross-sectional view and a partial enlarged view of the igniter of Example 1 of the present application are shown;

[0034] Figure 5 A schematic diagram of an insulating pad in the igniter of Example 1 of the present application is shown;

[0035] Figure 6 A schematic diagram of the lower housing in the igniter of Example 1 of the present application is shown;

[0036] Figure 7 A top view of the lower housing in the igniter of Example 1 of the present application is shown;

[0037] Figure 8 The schematic diagram of the igniter of Example 1 of the present application is shown. DETAILED DESCRIPTION

[0038] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0039] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In addition, the terms "primary" and "secondary" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "primary" and "secondary" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0041] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] In the present application, unless otherwise clearly specified and limited, when a main feature is “above” or “below” a second feature, it can mean that the main feature and the second feature are in direct contact, or the main feature and the second feature are in indirect contact through an intermediate medium. Moreover, when a main feature is “above”, “above” or “above” a second feature, it can mean that the main feature is directly above or obliquely above the second feature, or simply means that the main feature is higher in level than the second feature. When a main feature is “below”, “below” or “below” a second feature, it can mean that the main feature is directly below or obliquely below the second feature, or simply means that the main feature is lower in level than the second feature. Example

[0043] like Figure 1-Figure 8As shown, an embodiment of the present application provides an igniter, which is also called a cigarette lighter.

[0044] The igniter includes a metal shell 100 , a circuit board assembly 200 , an insulating pad 300 and a plug 400 .

[0045] The metal shell 100 includes an upper shell 101 and a lower shell 102, and the upper and lower shells 101 and 102 are threadedly matched. Specifically, the upper shell 101 is provided with an internal thread, and the lower shell 102 is provided with an external thread, and the internal and external threads are matched to achieve detachable matching. Of course, the internal and external thread structures here can be swapped. In addition, the upper and lower shells 101 and 102 can also be detachably matched on site by buckling, clamping, etc.

[0046] Here, the material of the metal housing 100 is brass. Of course, other metals can also be used in addition to brass, as long as it can have a stable shape.

[0047] The metal shell 100 here is generally in the shape of a three-dimensional gourd. The three-dimensional gourd shape includes an upper bulge and a lower bulge, and a contracted waist is provided between the upper and lower bulges. Here, the lower shell 102 is a part of the lower bulge, and the rest of the gourd-shaped structure is located on the upper shell 101.

[0048] The lower shell 102 includes a bottom plate 102a and a lower side wall 102b. The lower side wall 102b surrounds the bottom plate 102a. The lower side wall 102b is connected to the bottom plate 102a to form a first inner cavity. The first inner cavity has an upper opening 102c, and the orthographic projection area of ​​the upper opening 102c on the bottom plate 102a is S1. A first power extraction hole 102d is opened on the bottom plate 102a, and the first power extraction hole 102d is included by the orthographic projection area of ​​the upper opening 102c on the bottom plate 102a.

[0049] The upper shell 101 is a rotating body, and the upper shell 101 has a second inner cavity, and the second inner cavity and the first inner cavity form an installation space 103, and the installation space 103 here is used to install the circuit board assembly 200. A fire hole 101a is provided on the upper shell 101, and the fire hole 101a here can be closed by a plug 400. The plug 400 and the fire hole 101a are removably matched, and this removable fit can be that the plug 400 is directly inserted into the fire hole 101a, or the plug 400 and the hole wall of the fire hole 101a are threadedly connected, or a slight interference fit is formed between the plug 400 and the fire hole 101a (it can be removed with just a little force).

[0050] Here, the fire hole 101a is located close to the top of the gourd shape.

[0051] The circuit board assembly 200 includes a charging interface 201 , a charging management circuit 204 , a single chip microcomputer U2 , a battery BT1 and a heating wire assembly 203 .

[0052] The charging interface 201 uses a USB interface, specifically a type-c interface in the USB interface. In addition, other interfaces in the USB interface can also be used, such as Mirco-USB, type-a, type-b, etc. Of course, other charging interfaces 201 can also be used.

[0053] The charging interface 201 is fixed to the lower end of the circuit board substrate 202 and partially protrudes from the circuit board substrate 202 .

[0054] The insulating pad 300 includes a main body 301, and the size of the main body 301 is larger than the first power extraction hole 102d. A second power extraction hole 302 is provided on the main body 301, and the second power extraction hole 302 corresponds to the first power extraction hole 102d. The size of the second power extraction hole 302 here is consistent with the part of the USB interface that exceeds the circuit board substrate 202. In this way, the end of the circuit board substrate 202 with the charging interface 201 can be supported on the main body 301, and the charging interface 201 is exposed in the first power extraction hole 102d after passing through the second power extraction hole 302. Here, an annular protrusion 303 surrounding the second power extraction hole 302 is provided on the main body 301, and the annular protrusion 303 is located in the first power extraction hole 102d and is attached to the hole wall of the first power extraction hole 102d, that is, the annular protrusion 303 is located between the hole wall of the first power extraction hole 102d and the side of the charging interface 201. In this way, a limiting structure can be formed at the lower end of the circuit board assembly 200 by utilizing the charging interface 201, the insulating pad 300 and the bottom plate 102a.

[0055] The battery BT1 is directly soldered to the circuit board substrate 202, so that the battery BT1 and the circuit board substrate 202 can form a whole, which is very convenient for assembling the battery BT1.

[0056] The heating wire assembly 203 is fixed to the upper end of the circuit board substrate 202, and partially exceeds the circuit board substrate 202. The heating wire assembly 203 here uses a resistance wire ceramic heating plate. It is common knowledge that this resistance wire ceramic heating plate can generate heat to achieve the effect of ignition, and it will not be described in detail here. It is worth mentioning that this resistance wire ceramic heating plate has a gap, that is, airflow can pass through it.

[0057] Here, a mating protrusion 203a is provided on the periphery of the heating wire assembly 203, that is, the ceramic part of the resistance wire ceramic heating plate, and a limiting groove 101b is provided on the upper shell 101 near the ignition hole 101a. The mating protrusion 203a can extend into the limiting groove 101b to form a limiting fit. It is worth mentioning that a limiting structure is formed between the lower part of the circuit board assembly 200 through the charging interface 201, the insulating pad 300 and the bottom plate 102a, and the upper part of the circuit board assembly 200 can extend into the limiting groove 101b through the mating protrusion 203a to form a limiting fit, which can ensure that a stable installation structure is formed between the circuit board assembly 200 and the metal shell 100.

[0058] The circuit board substrate 202 and the metal housing 100 are not in direct contact, thus ensuring insulation performance.

[0059] Here, the orthographic projection area S2 of the circuit board assembly 200 on the bottom plate 102 a is greater than S2 , so that the circuit board substrate 202 can be prevented from contacting the lower side wall 102 b of the lower housing 102 .

[0060] Here, the specific circuit structure of the heating wire assembly 203 for heating is as follows:

[0061] The charging management circuit 204 includes a charging management chip U1 , a capacitor C1 , a resistor R1 , a resistor R2 , a resistor R6 , and a light emitting diode LED1 .

[0062] The charging management chip U1 here uses the model LTH7.

[0063] The VCC pin of the charging management chip U1 is electrically connected to the VBUS pin of the USB interface, one end of the resistor R1, one end of the resistor C1, and the RA0 / AN0 pin of the microcontroller U2 respectively.

[0064] The PROG pin of the charging management chip U1 is electrically connected to one end of the resistor R2.

[0065] The GND pin of the USB interface (that is, USB1), the other end of the capacitor C1, the other end of the resistor R1, and the other end of the resistor R2 are all grounded.

[0066] The cathode of the light emitting diode LED1 is grounded, the anode of the light emitting diode LED1 is electrically connected to one end of the resistor R6, and the other end of the resistor R6 is electrically connected to the AN11 / RB3 pin of the single chip microcomputer U2.

[0067] The CHRG pin of the charging management chip U1 is electrically connected to the AN8 / RB0 pin of the microcontroller U2.

[0068] The GND pin of the charging management chip U1 is grounded.

[0069] The BAT pin of the charging management chip U1 is connected to the positive electrode of the battery, and the negative electrode of the battery is grounded.

[0070] The positive electrode of the battery is connected to the VDD pin of the single-chip computer U2, and the positive electrode of the battery is connected to one end of the resistor L (that is, the resistor in the heating wire assembly 203).

[0071] The GND pin of the microcontroller U2 is grounded.

[0072] The VPR / RB2 pin and RA1AN1 pin of the single-chip microcomputer U2 are electrically connected to the air pressure sensing circuit 205. Here, the air pressure sensing circuit 205 includes a microphone M1, a transistor Q1, a capacitor C2, a resistor R3, and a resistor R4. The microphone M1 is an air pressure sensing element, and the microphone M1 is arranged close to the heating wire assembly 203, so that when the user blows, the air pressure can pass through the gap on the heating wire assembly 203 to the microphone M1. The negative electrode of the microphone M1 is grounded, the positive electrode of the microphone M1 is coupled to the B pole of the transistor Q1 through the capacitor C2, and the resistor R3 is electrically connected between the positive electrode of the microphone M1 and the RA1AN1 pin of the single-chip microcomputer U2. The C pole of the transistor Q1 is electrically connected to the VPR / RB2 pin of the single-chip microcomputer U2, the E pole of the transistor Q1 is grounded, and the resistor R4 is electrically connected between the B pole of the transistor Q1 and the E pole of the transistor Q1.

[0073] The RB1 / AN9 pin of the single-chip computer U2 is electrically connected to the gate of the MOS tube, the drain of the MOS tube is grounded, the drain of the MOS tube is connected to the other end of the resistor L (that is, the resistor in the heating wire assembly 203), and the source of the MOS tube is grounded. The resistor R5 is electrically connected between the source of the MOS tube and the gate of the MOS tube.

[0074] The principle of the above circuit is to charge the battery BT1 by using the USB interface and the charging management circuit 204. When the user blows air at the heating wire assembly 203, the microphone M1 senses the air pressure and converts the air pressure into an electrical signal, the transistor Q1 is turned on, the microcontroller U2 senses the change in high and low levels, the RB1 / AN9 pin outputs a high level, and the MOS tube is turned on, the battery BT1 supplies power to heat the resistor L. When the user does not blow air, the air pressure disappears, the transistor Q1 is turned off, the RB1 / AN9 pin of the microcontroller U2 no longer outputs a high level, the MOS tube is turned off, and the resistor L is no longer heated.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without contradiction.

[0076] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. An igniter, comprising a metal shell and a circuit board assembly, wherein a charging interface is fixed at one end of the circuit board assembly, and a heating wire assembly is fixed at the other end of the circuit board assembly; a battery is arranged on the circuit board assembly, the charging interface is used to charge the battery, and the battery is used to supply power to the heating wire assembly; the characteristics are: It also includes an insulating pad; the metal shell includes an upper shell and a lower shell, and the upper shell and the lower shell are each an integral part; the upper shell and the lower shell are detachably matched, and the two are matched to form an installation space for accommodating the circuit board assembly; a fire hole is provided on the upper shell, and the heating wire assembly is located in the fire hole; the lower shell includes a bottom plate, and a first power hole is provided on the bottom plate; the insulating pad includes a main body, and a second power hole is provided on the main body, and the size of the second power hole is smaller than the size of the first power hole, and the second power hole corresponds to the first power hole; the circuit board assembly has one end of a charging interface that is held against the main body, and the charging interface is exposed in the first power hole after passing through the second power hole.

2. The igniter according to claim 1, characterized in that: The insulating pad is provided with an annular protrusion, which surrounds the second power extraction hole; the annular protrusion is located between the hole wall of the first power extraction hole and the side surface of the charging interface.

3. The igniter according to claim 2, characterized in that: The upper shell is provided with a limiting groove at the ignition hole, and the heating wire assembly is provided with a matching protrusion, which extends into the limiting groove to form a limiting fit.

4. The igniter according to claim 2, characterized in that: The lower shell includes a lower side wall surrounding the bottom plate, the lower side wall is connected to the bottom plate to form a first inner cavity, and the first inner cavity is part of the installation space; The first inner cavity has an upper opening, the upper opening has an orthographic projection area S1 on the bottom plate, and the circuit board assembly has an orthographic projection area S2 on the bottom plate, and S1 is greater than S2.

5. The igniter according to claim 2, characterized in that: The circuit board assembly includes a circuit board substrate, and the circuit board substrate is not in direct contact with the metal housing.

6. The igniter according to claim 1, characterized in that: The metal shell is in a three-dimensional gourd shape.

7. The igniter according to claim 1, characterized in that: The charging interface is a USB interface; or / and, one of the upper shell and the lower shell is provided with an internal thread, and the other is provided with an external thread, and the internal thread and the external thread cooperate to form a detachable fit between the upper shell and the lower shell; and / or, the battery is welded to the circuit board assembly.

8. The igniter according to claim 1, characterized in that: It also includes a plug, which is removably matched with the fire-taking hole and is used to close the fire-taking hole.

9. The igniter according to claim 1, characterized in that: The circuit board assembly includes a charging management circuit, a single-chip microcomputer, an air pressure sensing circuit and a MOS tube; the charging interface is electrically connected to the charging management circuit, the charging management circuit is electrically connected to the single-chip microcomputer and the battery, and the charging interface charges the battery through the charging management circuit; the battery is electrically connected to the single-chip microcomputer and one end of the heating wire assembly to power the single-chip microcomputer and the heating wire assembly; the air pressure sensing circuit is electrically connected to the single-chip microcomputer to convert the external air pressure into an electrical signal and feed it back to the single-chip microcomputer; The single-chip microcomputer is connected to the gate of the MOS tube, the drain of the MOS tube is grounded, the drain of the MOS tube is connected to the other end of the heating wire assembly, and the source of the MOS tube is grounded; the single-chip microcomputer turns on the MOS tube according to the electrical signal converted by the air pressure sensing circuit to make the heating wire assembly heat up; the air pressure sensing element of the air pressure sensing circuit is arranged close to the heating wire assembly and is connected to the gap on the heating wire assembly.

10. The igniter according to claim 9, characterized in that: The air pressure sensing circuit includes a microphone, a transistor Q1, a capacitor C2, a resistor R3 and a resistor R4; the microphone is an air pressure sensing element, the negative electrode of the microphone is grounded, the positive electrode of the microphone is coupled with the B electrode of the transistor Q1 through the capacitor C2, and the resistor R3 is electrically connected between the positive electrode of the microphone and a pin of the single-chip computer; the C electrode of the transistor Q1 is electrically connected to a pin of the single-chip computer, the E electrode of the transistor Q1 is grounded, and the resistor R4 is electrically connected between the B electrode of the transistor Q1 and the E electrode of the transistor Q1.

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