Electromagnetic induction coil, electromagnetic induction apparatus, and cigarette heating appliance

Abstract

An electromagnetic induction coil, an electromagnetic induction apparatus, and a cigarette heating appliance. The electromagnetic induction coil comprises a coil body, which is formed by a conductor, wherein a hollow portion is provided inside the conductor. The interior of a wire of the coil body is hollow, and due to the existence of a skin effect, a current of a high-frequency circuit may be conducted on the surface of the conductor in a concentrated manner, and the circulation of the current is thus not affected by the hollow interior of the conductor. Moreover, the influence of the skin effect in the high-frequency circuit on the resistance of the coil body can also be reduced under the same cross-sectional area, thereby reducing equivalent resistance, reducing self-heating of the coil body, and improving the energy conversion utilization rate; and since the coil body uses the hollow conductor, materials can be saved on to a certain extent, and the weight of the appliance is reduced.

Description

Electromagnetic induction coil, electromagnetic induction device and cigarette heating device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on June 26, 2023, with application number 202310764333.0 and invention name “An electromagnetic induction coil, electromagnetic induction device and cigarette heating device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of heating tobacco without burning it, and in particular to an electromagnetic induction coil, an electromagnetic induction device and a cigarette heating device. Background Art

[0003] Due to its high heating efficiency, electromagnetic induction heating technology has begun to be applied to the heating technology of low-temperature cigarettes. The electromagnetic induction heating system for cigarettes uses a conductive material spirally wound around the outside of a heating chamber to form an inductor coil. An electronic control system generates an alternating current. This alternating current passes through the coil, generating heat within the conductor or magnetic receptor inside the coil due to hysteresis losses and eddy currents. The receptor can be placed inside or outside the cigarette. The heat generated by the receptor heats the smoking substance in the cigarette, producing a smokeable aerosol.

[0004] However, due to the skin effect of high-frequency current, the current will be concentrated on the surface of the coil conductor, while almost no current will flow through the central part of the conductor. This is equivalent to a reduction in the cross-section of the wire and an increase in resistance. Therefore, in electromagnetic induction heating devices, the coil will have a certain resistance loss, which will cause the coil itself to heat up, resulting in a decrease in energy conversion efficiency. At the same time, the heat generated by the coil will be conducted to the outer casing of the device, causing the outer casing temperature to increase, resulting in a poor holding experience.

[0005] Therefore, how to reduce the resistance loss of the electromagnetic induction coil, reduce the resistance of the coil conductor, and improve the energy utilization rate of electromagnetic heating is an urgent problem to be solved by those skilled in the art.

[0006] Summary of the Invention

[0007] To solve the above technical problems, the present application provides an electromagnetic induction coil, an electromagnetic induction device and a cigarette heating device, which can reduce the resistance loss of the electromagnetic induction coil, reduce the resistance of the induction coil conductor, and improve the electromagnetic heating energy utilization rate.

[0008] The technical solutions provided in this application are as follows:

[0009] An electromagnetic induction coil comprises a coil body formed by a conductor, wherein a hollow portion is provided inside the conductor.

[0010] Furthermore, the cross section of the conductor is circular, elliptical, triangular, square, rhombus or a polygon with more than four sides.

[0011] Furthermore, the cross section of the hollow portion inside the conductor is circular, elliptical, triangular, square, rhombus, or a polygon with four or more sides.

[0012] Furthermore, the cross-sectional shape of the hollow portion inside the conductor is the same as the cross-sectional shape of the conductor.

[0013] Furthermore, an air inlet is provided on the conductor at one end of the coil body, and an air outlet is provided on the conductor at the other end of the coil body, and the air inlet and the air outlet are respectively connected to the hollow portion inside the conductor.

[0014] An electromagnetic induction device comprises the electromagnetic induction coil and a circuit or power supply for providing alternating current to the electromagnetic induction coil.

[0015] A cigarette heating device comprises the electromagnetic induction coil described above, a circuit or power supply for providing alternating current to the electromagnetic induction coil, and a shell for accommodating the electromagnetic induction coil and the circuit or power supply. A accommodating cavity for placing a smoking substance is provided in the middle of the shell. When powered on, the electromagnetic induction coil generates an induced magnetic field to cause a heating element at least partially located inside the electromagnetic induction coil to generate heat, thereby heating the smoking substance.

[0016] Furthermore, the heating body is arranged inside the accommodating cavity, the electromagnetic induction coil is wound inside the shell, and the accommodating cavity is located inside the electromagnetic induction coil.

[0017] Furthermore, an air inlet is provided on the conductor at one end of the coil body close to the cigarette holder, and an air outlet is provided on the conductor at one end of the coil body away from the cigarette holder. The air inlet and the air outlet are respectively connected to the hollow portion inside the conductor, and an air inlet port is provided on the shell at a position corresponding to the air inlet port. The air inlet is connected to the outside through the air inlet port, and the air outlet is connected to the bottom of the accommodating cavity.

[0018] Furthermore, the heating body is in the shape of a column, a tube, a rod, a needle or a bar and is coaxially arranged with the electromagnetic induction coil;

[0019] Alternatively, the heating body is in a flat, sword-shaped, sheet-shaped or strip-shaped shape extending along the axial direction of the electromagnetic induction coil.

[0020] Furthermore, a magnetic shielding layer is provided outside the electromagnetic induction coil.

[0021] The present invention provides an electromagnetic induction coil, an electromagnetic induction device, and a cigarette heating device, wherein the conductor of the coil body is hollow inside. Due to the skin effect, the current of the high-frequency circuit will be concentrated and conducted on the surface of the conductor. Therefore, the hollowness of the conductor does not affect the flow of current. Moreover, under the condition of the same cross-sectional area, the influence of the skin effect in the high-frequency circuit on the resistance of the coil body can be reduced, the equivalent resistance can be reduced, the self-heating of the coil body can be reduced, and the energy conversion utilization rate can be improved. At the same time, the use of a hollow conductor in the coil body can also save materials to a certain extent and reduce the weight of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] FIG1 is a schematic structural diagram of a cigarette heating device according to an embodiment of the present application;

[0024] FIG2 is a cross-sectional view of the accommodating cavity of the cigarette heating device in the embodiment of the present application.

[0025] Reference numerals: coil body 1 , hollow portion 2 , shell 3 , accommodating cavity 4 , heating body 5 , air inlet 6 , power supply slot 7 . DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of this application.

[0027] It should be noted that when an element is referred to as being “fixed on” or “set on” another element, it can be directly on the other element or indirectly set on the other element; when an element is referred to as being “connected to” another element, it can be directly connected to the other element or indirectly connected to the other element.

[0028] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" or "several" means two or more, unless otherwise specifically defined.

[0030] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the efficacy and purpose that can be achieved by this application.

[0031] An embodiment of the present application provides an electromagnetic induction coil, comprising a coil body 1 formed of a conductor, wherein a hollow portion 2 is provided inside the conductor.

[0032] This embodiment provides an electromagnetic induction coil, in which the interior of the conductor of the coil body 1 is hollow, and the length of the hollow portion 2 inside the conductor is equal to the length of the conductor. Due to the existence of the skin effect, the current of the high-frequency circuit will be concentrated on the surface of the conductor for conduction. Therefore, the hollowness inside the conductor does not affect the flow of current. Moreover, when the cross-sectional area of ​​the conductor is the same, it can also reduce the influence of the skin effect in the high-frequency circuit on the resistance of the coil body 1, reduce the equivalent resistance, reduce the self-heating of the coil body 1, and improve the energy conversion utilization rate. At the same time, the use of a hollow conductor in the coil body 1 can also save materials to a certain extent and reduce the weight of the device.

[0033] Preferably, the cross-section of the conductor is circular, elliptical, triangular, square, rhombus, or a polygon with four or more sides. The cross-section of the conductor can specifically be a circular, elliptical, triangular, square, rhombus, or a regular polygon with four or more sides. The cross-section of the conductor referred to in this application refers to the outer shape of the conductor's cross section, and the middle of the conductor's cross section is hollow.

[0034] Specifically, the cross-section of the hollow portion 2 inside the conductor is circular, elliptical, triangular, square, rhombus, or a polygon with four or more sides. The cross-section of the hollow portion 2 inside the conductor can be a circular, elliptical, triangular, square, rhombus, or a regular polygon with four or more sides. The square can be a square or a rectangle. More specifically, the cross-section of the conductor can be a square, and the cross-section of the hollow portion 2 inside it can be a regular pentagon; or the cross-section of the conductor can be a triangle, and the cross-section of the hollow portion 2 inside it can be a circle.

[0035] This embodiment also provides an implementation method in which the cross-sectional shape of the hollow portion 2 inside the conductor is the same as the cross-sectional shape of the conductor. Specifically, if the cross-sectional shape of the conductor is circular, the cross-sectional shape of the hollow portion 2 inside the conductor is also circular; or, if the cross-sectional shape of the conductor is square, the cross-sectional shape of the hollow portion 2 inside the conductor is also square.

[0036] This embodiment further optimizes the above technical solution. An air inlet is provided on the conductor at one end of the coil body 1, and an air outlet is provided on the conductor at the other end of the coil body 1. The air inlet and the air outlet are respectively connected to the hollow part 2 inside the conductor.

[0037] Specifically, at least one air inlet and air outlet is provided, and preferably, multiple air inlet and air outlet can be provided. External air can enter the hollow portion 2 inside the conductor from the air inlet at one end of the coil body 1, then flow along the spiral inside the coil body 1, and finally flow out from the air outlet at the other end of the coil body 1. The temperature of the external air is relatively low. When the air flow flows through the hollow portion 2 inside the conductor of the coil body 1, due to a certain amount of heat generated by the coil body 1, the heat of the coil body 1 will preheat the gas flowing inside. Moreover, since the coil body 1 is spirally wound, the flow path of the gas inside the coil body 1 is longer, and the preheating length of the air flow is increased, which is beneficial for preheating the internal gas and helps to reduce the temperature of the coil body 1 itself.

[0038] This embodiment also provides an electromagnetic induction device, comprising the aforementioned electromagnetic induction coil and a circuit or power supply for providing alternating current to the electromagnetic induction coil. This electromagnetic induction device also has the beneficial effects of the aforementioned electromagnetic induction coil, reducing resistance loss, equivalent resistance, and self-heating of the coil body 1, thereby effectively reducing energy loss and improving electromagnetic heating energy utilization.

[0039] This embodiment also provides a cigarette heating device, as shown in Figures 1 and 2, comprising the above-mentioned electromagnetic induction coil, a circuit or power supply for providing alternating current to the electromagnetic induction coil, and a shell 3 for accommodating the electromagnetic induction coil and the circuit or power supply. A accommodating cavity 4 for placing a smoking substance is provided in the middle of the shell 3. When powered on, the electromagnetic induction coil generates an induced magnetic field to cause a heating body 5 at least partially located inside the electromagnetic induction coil to generate heat for heating the smoking substance.

[0040] Specifically, the electromagnetic induction coil and the power supply or circuit are disposed inside the housing 3. When smoking tobacco or other smokable substances, the tobacco is placed in the receiving chamber 4. The tobacco itself may include a heater 5, but the heating device itself does not include the heater 5. The tobacco with the heater 5 is located inside the electromagnetic induction coil. When energized, the electromagnetic induction coil generates an induced magnetic field. The heater 5 generates heat under the action of the magnetic field of the electromagnetic induction coil, and the heater 5 heats the tobacco. Of course, the heater 5 can be fixedly disposed inside the housing 3, and the heater 5 is at least partially located inside the electromagnetic induction coil. After the tobacco is placed in the receiving chamber 4, the heater 5 generates heat under the action of the magnetic field of the electromagnetic induction coil, thereby heating the tobacco inside the receiving chamber 4.

[0041] The heating element 5 can be made of electrically conductive or magnetic materials and can generate heat under the influence of the magnetic field of the electromagnetic induction coil. Specifically, the heating element 5 can be made entirely of metal; or, alternatively, a metal-containing heating structure composed of metal and electrically insulating materials, such as a ceramic substrate coated with a metallic conductive material. Preferably, the housing 3 is made of an insulating material, such as ceramic or a high-temperature resistant insulating polymer. The housing 3 is preferably made of ceramic, which provides excellent insulation and heat isolation.

[0042] In this embodiment, a power supply slot 7 and a circuit board are provided at one end of the housing 3 away from the accommodating chamber 4. The power supply slot 7 is used to accommodate a battery power source. The positive and negative terminals of the power supply slot 7 are electrically connected to the control circuit on the circuit board, which is electrically connected to the electromagnetic induction coil. The battery is used to provide an alternating current to the electromagnetic induction coil via the control circuit. Of course, the control circuit can also be directly electrically connected to an external power source to provide alternating current to the electromagnetic induction coil. A control button can be provided on the housing 3, connected to the control circuit, for controlling whether the power source powers on or off the electromagnetic induction circuit.

[0043] This embodiment optimizes the above-mentioned technical solution. The heater 5 is positioned within the accommodating cavity 4. The electromagnetic induction coil is wound within the housing 3, with the accommodating cavity 4 located within the electromagnetic induction coil. Specifically, the housing 3 comprises an inner shell and an outer shell. The electromagnetic induction coil is wound around the outside of the inner shell and positioned between the two. The accommodating cavity 4 is positioned in the middle of the inner shell, and the heater 5 is coaxially positioned at the bottom of the accommodating cavity 4. When tobacco material is placed in the accommodating cavity 4, the heater 5 is inserted into the middle of the material from the bottom, heating the material from the center.

[0044] Preferably, in this embodiment, an air inlet is provided on the conductor at one end of the coil body 1 close to the cigarette holder, and an air outlet is provided on the conductor at the end of the coil body 1 away from the cigarette holder. The air inlet and the air outlet are respectively connected to the hollow portion 2 inside the conductor, and an air inlet 6 is provided on the shell 3 at a position corresponding to the air inlet. The air inlet is connected to the outside through the air inlet 6, and the air outlet is connected to the bottom of the accommodating cavity 4.

[0045] The air path design of existing cigarette heating devices is generally to introduce cold air from the outside directly into the interior of the heating chamber. When the airflow enters the heating chamber, due to the low airflow temperature, it will cause the internal temperature of the tobacco and the temperature of the heating element to drop suddenly, resulting in a poor smoking taste. In addition, the control system will quickly increase the power for temperature compensation and increase the temperature of the heating element, which will lead to increased energy consumption.

[0046] In the cigarette heating device provided in this embodiment, the conductor of the coil body 1 at the end closest to the mouthpiece is provided with one or more air inlet holes, and the conductor at the end further from the mouthpiece is provided with one or more air outlet holes. The air inlet holes and the air outlet holes are connected through a hollow portion 2 within the conductor. When the smoker draws in from the mouthpiece, external air flows into the conductor through the air inlet 6 of the heating device housing, spirals through the hollow portion 2 within the conductor, and finally flows out of the air outlet holes of the coil body 1, enters the bottom of the accommodating cavity 4, and reaches the end of the cigarette. As the smoker draws in, the air enters the cigarette and, along with the aerosol generated by the smokable substances in the tobacco material, enters the smoker's cavity, as specifically indicated by the arrows in Figure 1. Since the conductor of the coil body 1 generates a certain amount of heat, when the air flow flows through the hollow part 2 of the conductor, the heat of the conductor will preheat the air flow flowing through the hollow part 2 inside it, and since the coil body 1 is spirally wound, the flow path of the air flow in the hollow part 2 inside the conductor is longer, and the preheating length of the air flow is increased. When the air flow reaches the air outlet of the coil body 1 and reaches the end of the cigarette, the temperature of the air flow is significantly higher than the ambient temperature. At this time, when the air flow enters the interior of the cigarette again, the impact on the temperature inside the cigarette and the temperature of the heating body 5 is reduced, and it will not cause a sharp drop in temperature instantaneously. The control system only needs to maintain a stable output power to maintain the stability of the entire temperature field inside the cigarette, which is beneficial to maintaining the consistency of the smoking taste and also helps to reduce energy consumption.

[0047] Furthermore, due to the resistance loss of the coil body 1, it generates heat. This heat is then transferred to the outer shell of the heating device, raising the temperature of the outer shell and causing a poor grip experience for the user. When the cooler airflow passes through the conductor, it helps to lower the temperature of the coil body 1, thereby cooling the outer shell 3.

[0048] Furthermore, the heating body 5 is in a columnar, tubular, rod-shaped, needle-shaped or bar-shaped shape coaxially arranged with the electromagnetic induction coil; or, the heating body 5 is in a flat, sword-shaped, sheet-shaped or strip-shaped shape extending along the axial direction of the electromagnetic induction coil.

[0049] In this embodiment, the heating body 5 adopts the above-mentioned shape and structure, which not only facilitates the heating body 5 to heat the cigarette in the receiving cavity 4, but also facilitates the heating body 5 to be inserted into the cigarette. Preferably, the heating end is pointed.

[0050] In order to prevent electromagnetic leakage, a magnetic shielding layer is provided on the outside of the electromagnetic induction coil. The magnetic shielding layer can effectively prevent electromagnetic leakage.

[0051] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An electromagnetic induction coil, characterized in that: The invention comprises a coil body formed of a conductor, wherein a hollow portion is provided inside the conductor.

2. The electromagnetic induction coil according to claim 1, characterized in that: The cross section of the conductor is circular, elliptical, triangular, square, rhombus or a polygon with more than four sides.

3. An electromagnetic induction coil according to claim 1 or 2, characterized in that: The cross section of the hollow portion inside the conductor is circular, elliptical, triangular, square, rhombus, or a polygon with more than four sides.

4. An electromagnetic induction coil according to claim 1 or 2, characterized in that: The cross-sectional shape of the hollow portion inside the conductor is the same as the cross-sectional shape of the conductor.

5. The electromagnetic induction coil according to claim 3, characterized in that: An air inlet is provided on the conductor at one end of the coil body, and an air outlet is provided on the conductor at the other end of the coil body. The air inlet and the air outlet are respectively connected to the hollow part inside the conductor.

6. An electromagnetic induction device, characterized in that: It comprises the electromagnetic induction coil as claimed in any one of claims 1 to 5 and a circuit or power supply for providing alternating current to the electromagnetic induction coil.

7. A cigarette heating device, characterized in that: It comprises the electromagnetic induction coil as described in any one of claims 1 to 5, a circuit or power supply for providing alternating current to the electromagnetic induction coil, and a shell for accommodating the electromagnetic induction coil and the circuit or power supply, wherein a accommodating cavity for placing a smoking substance is provided in the middle of the shell, and when powered on, the electromagnetic induction coil generates an induced magnetic field so that a heating body at least partially located inside the electromagnetic induction coil generates heat, thereby heating the smoking substance.

8. The cigarette heating device according to claim 7, characterized in that: The heating body is arranged inside the accommodating cavity, the electromagnetic induction coil is wound inside the shell, and the accommodating cavity is located inside the electromagnetic induction coil.

9. A cigarette heating device according to claim 7 or 8, characterized in that: An air inlet is provided on the conductor at one end of the coil body close to the cigarette holder, and an air outlet is provided on the conductor at one end of the coil body away from the cigarette holder. The air inlet and the air outlet are respectively connected to the hollow part inside the conductor, and an air inlet port is provided at a position corresponding to the air inlet on the shell. The air inlet is connected to the outside through the air inlet port, and the air outlet port is connected to the bottom of the accommodating cavity.

10. The cigarette heating device according to claim 9, characterized in that: The heating body is in the shape of a column, a tube, a rod, a needle or a bar and is coaxially arranged with the electromagnetic induction coil; Alternatively, the heating body is in a flat, sword-blade, sheet or strip shape extending along the axial direction of the electromagnetic induction coil.

11. A cigarette heating device according to claim 7 or 8, characterized in that: A magnetic shielding layer is arranged outside the electromagnetic induction coil.

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