Electromagnetic induction heating coil and manufacturing method thereof

Abstract

Disclosed are an electromagnetic induction heating coil and a method for manufacturing the same, the heating coil including a conductive portion that generates a magnetic field when a current passes through the conductive portion, and a cladding portion that closely winds the conductive portion from an outer periphery and defines a cross-sectional shape thereof perpendicular to a current direction, the conductive part comprises a plurality of strands of conductive wires, and is characterized in that the conductive part is limited in a space with a rectangular cross section by the coating part, the conductive wires are wires with polygonal cross sections, and the conductive wires meet the condition that C: S is greater than 45mm <-1 >. According to the heating coil, the electrified sectional area can be effectively utilized, meanwhile, the influence of the skin effect is smaller, the safe current-carrying capacity of a coil conductive wire can be effectively increased, coil heating during working of an electromagnetic induction appliance is effectively improved, and the heating coil is smaller in relative size, thinner in thickness and easier to produce and wind.

Description

Technical Field

[0001] The invention belongs to the technical field of novel electromagnetic induction heating devices, and in particular relates to an electromagnetic induction heating coil and a manufacturing method thereof. Background Art

[0002] Electromagnetic induction heating technology, with its high heating efficiency, has gradually been applied to the heating technology field of low-temperature cigarettes. In the electromagnetic induction heating system, heating is achieved by placing a conductive material outside the heating chamber to construct an electromagnetic heating coil. When the electronic control system generates alternating currents, these currents flow through the coil, causing hysteresis losses and eddy current effects, which in turn generate heat in the conductor or magnetic receptors inside the coil. These receptors can be flexibly arranged inside or outside the cigarette, and the heat they generate can effectively bake and heat the smoking substances in the cigarette, prompting it to produce aerosols that can be inhaled by consumers.

[0003] The electromagnetic heating coil of the current electromagnetic induction heating device is usually formed by bending a round thin conductive wire, such as Fig. 9 As shown. The utilization rate of the energized cross-section of the heating coil is reduced for the following reasons: In a DC circuit, the current is evenly distributed on the cross-section of a uniform conductive wire, that is, the current density on the cross-section of a uniform conductive wire is uniform. In an AC circuit, the current density on the cross-section of a uniform conductive wire becomes uneven, which is related to the frequency of the current. As the current frequency increases, the closer the current density is to the surface of the conductive wire on the cross-section of the conductive wire, the greater the current density. This phenomenon is called the skin effect. Due to the skin effect, most of the current will be concentrated in a ring surface with a thickness equal to the skin depth. The skin effect reduces the effective area of ​​the conductor, thereby increasing the equivalent resistance of the conductor. The skin depth is related to the current frequency, the electrical conductivity and the magnetic permeability of the conductor. According to the relevant theory of electromagnetic induction, in high-frequency circuits, the current mainly flows on the surface of the conductor. The further into the conductor, the smaller the current is. The skin depth is used to describe this phenomenon. The calculation formula for the skin depth is:

[0004]

[0005] Where f is the operating frequency, and the magnetic permeability μ and electrical conductivity σ are determined by the properties of the material itself. It can be seen that when the conductive wire material is selected, the skin depth is inversely proportional to the square root of the frequency.

[0006] Although some coil solutions have been proposed for large-scale engineering equipment, these coils are bulky and expensive and are not suitable for handheld electronic heating devices. Summary of the invention

[0007] In order to solve the technical problem that the coil in the electromagnetic heating device generates a large amount of heat due to the small cross-sectional area of ​​the existing heating coil and the problems in the selection, resulting in the increase of the shell temperature and the waste of energy, the present invention provides an electromagnetic induction heating coil and a manufacturing method thereof, thereby optimizing the coil heating problem and improving the energy efficiency.

[0008] The technical solution adopted by the present invention is:

[0009] An electromagnetic induction heating coil, the heating coil comprising a conductive portion (10) and a covering portion (20), wherein when current passes through the conductive portion (10), the heating coil generates a magnetic field, the covering portion (20) tightly winds the conductive portion (10) from the periphery and defines a cross-sectional shape perpendicular to the current direction, the conductive portion (10) comprises a plurality of conductive wires (11), characterized in that the covering portion (20) defines the conductive portion (10) within a rectangular cross-sectional space, the conductive wires (11) are polygonal cross-sectional wires, and the conductive wires (11) satisfy the following conditions:

[0010] C:S>45mm -1

[0011] Wherein: C is the cross-sectional perimeter of the conductive wire; S is the cross-sectional area of ​​the conductive wire.

[0012] Furthermore, the rectangular cross section satisfies the following conditions:

[0013] L:W≥2:1

[0014] Wherein: L is the length of the rectangular cross section; W is the width of the rectangular cross section.

[0015] Furthermore, the rectangular cross section satisfies the following conditions:

[0016] W:L≥2:1

[0017] Wherein: L is the length of the rectangular cross section; W is the width of the rectangular cross section.

[0018] Furthermore, the conductive wire (11) satisfies:

[0019] 50mm -1 <C:S<200mm -1 .

[0020] Furthermore, the conductive wires (11) can be spliced ​​together and can be infinitely expanded.

[0021] Furthermore, the cross-sectional shape of the conductive wire (11) is a random polygon or a tile family pattern.

[0022] Furthermore, the area of ​​the rectangular cross section is 1.5 mm 2 ~4.5mm 2 The number of the conductive wires (11) is 50 to 500.

[0023] A method for manufacturing the electromagnetic induction heating coil, characterized in that the manufacturing method comprises the following steps:

[0024] Step 1: Determine the coil cross-sectional area A1 based on the selected conductive wire material and the current carrying capacity of the aerosol generating device;

[0025] Step 2: According to the material of the conductive wire and the operating frequency of the aerosol generating device, the diameter of the conductive wire is selected by calculating the skin depth, thereby determining the cross-sectional area A2 of the selected conductive wire;

[0026] Step 3: Obtain the range of the number of strands of the selected conductive wire material by the ratio of A1 and A2;

[0027] Step 4: Gather the above number of conductive wires into a bundle;

[0028] Step 5: tightly wrap the coating portion around the outer periphery of the conductive wire bundle to obtain the initial product of the electromagnetic induction heating coil;

[0029] Step 6: Pressing the heating coil primary product into a rectangular outline raw material by a pressure device;

[0030] Step 7: Wind the pressed raw material to obtain an electromagnetic induction heating coil.

[0031] Furthermore, the specific operation steps of step 4 are as follows:

[0032] Step 41: spraying the selected conductive wires with a spray of a bonding material evenly to form a uniform bonding material coating on the surface of each conductive wire;

[0033] Step 42: Arrange the conductive wires with the bonding material coating in parallel; or twist the conductive wires with the bonding material coating into multiple strands.

[0034] A method for manufacturing the electromagnetic induction heating coil, characterized in that the manufacturing method comprises the following steps:

[0035] Step 1: Determine the coil cross-sectional area A1 based on the selected conductive wire material and the current carrying capacity of the aerosol generating device;

[0036] Step 2: According to the material of the conductive wire and the operating frequency of the aerosol generating device, the diameter of the conductive wire is selected by calculating the skin depth, thereby determining the cross-sectional area A2 of the selected conductive wire;

[0037] Step 3: Obtaining the selected strand number range of the conductive wire material through the ratio of A1 and A2;

[0038] Step 4: Processing the conductive wire to obtain a polygonal cross-section, wherein the polygons can be spliced ​​together to be infinitely expanded;

[0039] Step 5: Arrange the conductive wires in parallel and connect them to form a bundle;

[0040] Step 6: tightly wrap the coating portion around the outer periphery of the conductive wire bundle to obtain a preliminary electromagnetic induction heating coil;

[0041] Step 7: Pressing the coil into a rectangular shape by a pressure device;

[0042] Step 8: Winding the raw material into a shape to obtain an electromagnetic induction heating coil.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] 1. The present invention designs the coil cross-section and the conductive wire therein. Under the condition of the same area, the circumference of the conductive wire is longer, which can effectively avoid the skin effect, the effective area through which the total current flows is larger, and the equivalent resistance is smaller. Therefore, the electromagnetic induction heating coil can effectively reduce the energy loss caused by resistance.

[0045] 2. The present invention effectively utilizes space, which not only ensures that the induction coil can carry current safely and improves the heating condition of the induction coil, but also makes the overall volume of the induction heating coil smaller, which is more in line with the needs of small electronic devices such as aerosol heating devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a three-dimensional half-section view of the heating coil in Example 1 of the present invention;

[0047] Figure 2 is a cross-sectional view of the coil in Example 1 of the present invention;

[0048] Figure 3 is a three-dimensional schematic diagram of a heating coil in Embodiment 2 of the present invention;

[0049] Figure 4 is a cross-sectional view of the coil in Example 2 of the present invention;

[0050] Figure 5is a cross-sectional view of a heating coil according to Embodiment 3 of the present invention;

[0051] Figure 6 is a three-dimensional cross-sectional view of embodiment 4 of the present invention;

[0052] Figure 7 is a cross-sectional view of a heating coil according to Embodiment 5 of the present invention;

[0053] Figure 8 is a cross-sectional view of a heating coil according to Embodiment 6 of the present invention;

[0054] Fig. 9 It is a stereogram of a conventional enameled wire coil in the prior art;

[0055] Fig.10 is a schematic cross-sectional view of an aerosol generating device.

[0056] The reference numerals are described as follows:

[0057] Induction heating coil: 1, 1'

[0058] Conductive part: 10, 10'

[0059] Covering: 20, 20'

[0060] Conductive wire: 11, 11'

[0061] Receptors: 30

[0062] Power: 40

[0063] Heater bracket: 50

[0064] Cigarettes: 90

[0065] Conductive wire circumference: C

[0066] Conductive wire area: S

[0067] Rectangular section length: L

[0068] Rectangular section width: W. DETAILED DESCRIPTION

[0069] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0070] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0071] The present invention will be described in detail below in conjunction with exemplary embodiments with reference to the accompanying drawings.

[0072] The cross-sectional direction refers to the cross-sectional direction perpendicular to the current direction.

[0073] In order to make the purpose, technical solutions and advantages of this patent clearer, the implementation method of this patent will be further described in detail below in conjunction with the accompanying drawings.

[0074] The heating coil of the existing heat-not-burn smoking device is usually a coil formed by bending a round thin enameled wire, such as Fig. 9 As shown. The utilization rate of the energized cross-section of the heating coil is not ideal. The main reason is that due to the skin effect, the current is equivalent to flowing only on the surface of the conductive wire, which is equivalent to comparing the circumference of the two figures. The circle is the geometric figure with the largest area under the same circumference. Therefore, the efficiency of the conductive wire with a circular cross-section is not high in passing high-frequency electricity, because the internal area is not utilized. For this reason, coils composed of multiple strands of fine enameled wires have gradually appeared. The main structure of this type of coil is that multiple strands of round conductive wires are wrapped under a circular shell. Even if the round conductive wires are closely arranged to form multiple strands of enameled wires, there must be cavities between the circles. This part of the cavity occupies the area, but it is not energized. This is also the main reason why the entire multi-strand enameled wire needs a larger total cross-sectional diameter under the same energized cross-section. This causes the volume of the entire device to become larger and cannot meet the current consumer demand.

[0075] The multi-strand enameled copper wire is generally cylindrical, and the diameter of a single thin wire is generally 0.05mm to 0.1mm. It needs to be determined according to the frequency of the working environment. The method of determination is to calculate the skin depth. According to the relevant theory of electromagnetic induction, in high-frequency circuits, the current mainly flows on the surface of the conductor. The closer to the conductor, the smaller the current. The skin depth is used to describe this phenomenon. The calculation formula of skin depth is:

[0076]

[0077] Where f is the operating frequency

[0078] For copper conductive wire, magnetic permeability μ=4π×10 -7 H / m;

[0079] Conductivity σ=57142857S / m;

[0080] After being brought into the calculation, it is simplified to:

[0081]

[0082] Assuming f=100kHz, δ≈0.2mm; assuming f=1MHz, δ≈0.02mm.

[0083] When selecting copper wire, in order to ensure that most of the cross-sectional area of ​​the copper wire can carry a large current, the diameter of the copper wire is usually required to be less than twice the skin depth at its operating frequency. For general electromagnetic induction equipment, the operating frequency is usually at the hundreds of k level. In this working environment, selecting a copper wire with a diameter of 0.1mm can improve the area utilization. However, according to the experience of electrical engineering, the safe current density of copper conductive wire is about 5A / mm 2 If the current carrying capacity exceeds this value, the coil will generate serious heat. Considering that the current carrying capacity of the electromagnetic heating device coil is usually between 10A and 20A, if we take the middle value of 15A for estimation, at least 3mm 2 The cross section of the conductive wire must be 3mm to ensure that the coil conductive wire will not overheat, which will affect the use of the equipment. For multi-strand enameled wire composed of round thin wires with a diameter of 0.1mm, the cross section of the conductive wire must be 3mm 2 To meet the cross-sectional area, about 400 strands of such thin wire are needed. The total outer diameter of the currently available multi-strand enameled wire products is about 2.8mm. This means that at least 5.6mm of space needs to be reserved on both sides of the bracket of the electromagnetic heating device to place the coil, which is obviously a disadvantage for electromagnetic heating devices that pursue product miniaturization. Considering the size, the actual compromise is generally to select about 100 strands of multi-strand enameled wire as the coil winding. The total outer diameter after compounding is 1.35mm, but its cross-sectional area is only 0.784mm 2 , the safe current carrying capacity is only 3.92A. This is the main reason why the coils on current electromagnetic heating appliances heat up seriously, consume high energy and are hot to the touch.

[0084] The present invention provides an electromagnetic induction heating coil which can effectively avoid the skin effect and will not cause overheating due to size reduction. The specific scheme is as follows:

[0085] Example 1

[0086] like Figure 1 , Figure 2 FIG. 1 is a three-dimensional half-section view of an induction heating coil 1 according to Embodiment 1 of the present invention. The cross section of the wire wound around the coil is rectangular. In this embodiment, the covering portion 20 covers the outer periphery of the conductive portion 10 and limits the conductive portion 10 to a rectangular cross section. The conductive portion 10 includes a conductor and can conduct current. When the current passes through the conductive portion 10, the heating coil can generate a magnetic field to cause the heat receiving body 30 disposed in the heating coil to heat up. The rectangular cross section satisfies:

[0087] W:L≥2:1

[0088] Where: L is the length of the rectangle; W is the width of the rectangle.

[0089] Specifically, W:L=3.

[0090] Specifically, the rectangular cross-sectional area of ​​the coil is 1.5 mm 2 ~4.5mm 2 between.

[0091] Example 2

[0092] like Figure 3 , Figure 4 , which is a stereoscopic view of an induction heating coil 1 according to Embodiment 2 of the present invention. This embodiment is a variant of Embodiment 1, but the outer contour is different from that of Embodiment 1. The cross section of the wire wound around the coil is rectangular. In this embodiment, the covering portion 20' covers the outer periphery of the conductive portion and confines the conductive portion to a rectangular cross section. When current passes through the conductive portion 10, the heating coil can generate a magnetic field to heat the susceptor disposed in the heating coil. The conductive portion includes a plurality of conductive wires 11. The rectangular cross section of the coil satisfies:

[0093] L:W≥2:1

[0094] Where: L is the length of the rectangle; W is the width of the rectangle.

[0095] Specifically, L:W=3.

[0096] Specifically, the rectangular cross-sectional area of ​​the coil is 1.5 mm 2 ~4.5mm 2 between.

[0097] Embodiment 3:

[0098] See also Figure 5 , is a schematic cross-sectional view of the conductive wire 11 in Example 3, in which the covering portion 20 covers the outside of the conductive wire 11; specifically, the cross-section of the conductive wire 11 is a hat shape, including a concave structure and an acute-angle protrusion.

[0099] The conductive part 10 is composed of a plurality of conductive wires 11, and the hat shape satisfies:

[0100] C:S>60mm -1

[0101] Wherein: C is the cross-sectional perimeter of the conductive wire; S is the cross-sectional area of ​​the conductive wire.

[0102] Embodiment 4:

[0103] Embodiment 4 is a variation of the multiple strands of conductive wire 11 in Embodiment 3, wherein the covering portion 20' covers the outside of the conductive wire 11'; specifically, the multiple strands of conductive wire are in random polygonal shapes and are different from each other and closely arranged, see Figure 6 . The polygon satisfies:

[0104] C:S>45mm -1

[0105] Wherein: C is the circumference of the conductive wire; S is the area of ​​the conductive wire.

[0106] Embodiment 5:

[0107] See also Figure 7 , is a schematic cross-sectional view of the heating coil in Example 5, and the specific shape is a regular hexagon.

[0108] Embodiment 6:

[0109] See also Figure 8 , is a schematic cross-sectional view of the heating coil in Example 6, and the specific shape is a Penrose tile pattern.

[0110] In combination with the aforementioned embodiments 3-6, it is easy to understand that any tile family pattern of conductive wires that can fill a rectangular cross-section is feasible.

[0111] In other embodiments, the conductive wire is pre-processed to form a specific cross-sectional shape, which can be spliced ​​with each other to form a tile family pattern with an infinitely expanded area. Optionally, the cross-sectional shape of the conductive wire can be a triangle, rectangle, pentagon, hexagon, etc. Preferably, the conductive wire includes a recessed edge, and such a cross-sectional shape can have a larger perimeter with the same area.

[0112] In some embodiments, the periphery of each conductive wire includes a bondable coating (not shown). The bondable coating is a state that can be activated (e.g., by heating) so that the conductive wire is bonded to another adjacent conductive wire. The bondable coating allows each conductive wire to form a rectangular cross-section of the electromagnetic induction heating coil in the coating, and after the bondable coating is activated, the electromagnetic induction heating coil will maintain the shape. The shape of the heating coil is constrained by the bondable coating.

[0113] Alternatively, the bondable coating layer may be an electrical insulation layer of the conductive wire. The bondable coating layer and the insulation layer may also be separate layers from each other, and the bondable coating layer surrounds the outer circumference of the insulation layer.

[0114] In some embodiments, the number of the conductive wires is 50 to 500.

[0115] Preferably, the number of the conductive wires (11) is 100 to 400.

[0116] Manufacturing process example 1:

[0117] In some embodiments (for example, in Embodiment 4, each of the multiple strands of wire is in an irregular pattern), the processing method of the electromagnetic induction heating coil includes the following steps:

[0118] Step 1: Determine the conductive wire cross-section A1 of the coil according to the selected conductive wire material (usually copper wire) and the current carrying capacity of the heating device (usually 10A to 20A);

[0119] Step 2: According to the material of the conductive wire and the operating frequency of the heating device, the diameter of the conductive wire is selected by calculating the skin depth, thereby determining the cross-sectional area A2 of the selected conductive wire;

[0120] Step 3: The ratio of A1 to A2 can be used to obtain the number of strands of the selected conductive wire;

[0121] Step 4: Gather the above number of conductive wires into a bundle;

[0122] Step 5: Wrap the covering portion tightly around the outer periphery of the conductive wire bundle to obtain an original wire bundle;

[0123] Step 6: Press the original wire harness into the required contour shape through a pressure device;

[0124] Step 7: Wind the pressed wire to obtain an electromagnetic induction heating coil.

[0125] As a further solution of the present invention, in step 4, a selected number of conductive wires may be sprayed with a bondable coating and then assembled after spraying.

[0126] Optionally, when the conductive wires are assembled into a bundle, the individual conductive wires may be arranged in a variety of ways, and each conductive wire may be a twisted multiple-strand wire, or may be conductive wires arranged parallel to each other.

[0127] Manufacturing process example 2:

[0128] In some other embodiments (such as Embodiment 3), the electromagnetic induction heating coil manufacturing method includes the following steps:

[0129] Step 1: Determine the coil cross-sectional area A1 based on the selected conductive wire material and the current carrying capacity of the aerosol generating device;

[0130] Step 2: According to the material of the conductive wire and the operating frequency of the aerosol generating device, the diameter of the conductive wire is selected by calculating the skin depth, thereby determining the cross-sectional area A2 of the selected conductive wire;

[0131] Step 3: Obtain the number of strands of the selected conductive wire material through the ratio of A1 and A2;

[0132] Step 4: Process the conductive wire to obtain a polygonal cross-section, and the polygons can be spliced ​​together to expand infinitely;

[0133] Step 5: Arrange the conductive wires in parallel and connect them together into a bundle;

[0134] Step 6: Wrap the covering portion tightly around the outer periphery of the conductive wire bundle to obtain a preliminary product of the electromagnetic induction heating coil;

[0135] Step 7: Press the original wire harness into the required contour shape through a pressure device;

[0136] Step 8: Wind the pressed wire to obtain an electromagnetic induction heating coil.

[0137] As a further solution in this embodiment, in step 4, a selected number of conductive wires may be sprayed with a bondable coating and then assembled after spraying.

[0138] like Fig.10 As shown, the aerosol generating device using the heating coil of the present invention includes a heating coil, a heater bracket 50, a receptor 30, and a power source 40.

[0139] A power source 40 is connected to the heating coil and is configured to provide a high frequency current to the heating coil. In use, the heating coil generates a fluctuating electromagnetic field to heat the susceptor in thermal contact with the cigarette 90 and thereby heat the aerosol generating substrate.

[0140] The electromagnetic heating component can be of external heating type or internal heating type.

[0141] The heating coil is connected to the main control circuit by welding or plugging. Preferably, the electromagnetic heating assembly further includes a temperature sensor (not shown in the figure) for feeding back the temperature of the sensor 30 .

[0142] The heating coil and the susceptor 30 are fixedly mounted on the heater bracket 50. The inner space of the heater bracket 50 forms a heating chamber; the heating chamber is used to accommodate and heat cigarettes.

[0143] The present invention designs the coil cross section and the conductive wire therein. Under the condition of the same area, the circumference of the conductive wire is longer, which can effectively avoid the skin effect, the effective area through which the total current flows is larger, and the equivalent resistance is smaller. Therefore, the electromagnetic induction heating coil can effectively reduce the energy loss caused by the resistance. And because of the effective use of space, the coil can not only ensure that the induction coil carries current safely, the heating condition of the induction coil is improved, but also the overall volume of the induction heating coil is smaller, which is more in line with the needs of small electronic devices such as aerosol heating devices.

[0144] In the description of the present invention, it is to 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”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention 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 limiting the present invention.

[0145] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0146] In the present invention, 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 one; it can be a mechanical connection, an electrical connection, or communication with each other; 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, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0147] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0148] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 invention. In this specification, the schematic representations of the above terms do 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 the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0149] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An electromagnetic induction heating coil, comprising a conductive portion (10) and a covering portion (20), wherein: When current passes through the conductive part (10), the heating coil generates a magnetic field, the covering part (20) tightly winds the conductive part (10) from the periphery and defines its cross-sectional shape perpendicular to the current direction, the conductive part (10) comprises a plurality of conductive wires (11), and is characterized in that the covering part (20) defines the conductive part (10) within a rectangular cross-sectional space, the conductive wires (11) are polygonal cross-sectional wires, and the conductive wires (11) satisfy the following conditions: C:S>45mm -1 Wherein: C is the cross-sectional perimeter of the conductive wire; S is the cross-sectional area of ​​the conductive wire.

2. The electromagnetic induction heating coil according to claim 1, characterized in that: The rectangular cross section meets the following conditions: L:W≥2:1 Wherein: L is the length of the rectangular cross section; W is the width of the rectangular cross section.

3. The electromagnetic induction heating coil according to claim 1, characterized in that: The rectangular cross section meets the following conditions: W:L≥2:1 Wherein: L is the length of the rectangular cross section; W is the width of the rectangular cross section.

4. The electromagnetic induction heating coil according to claim 1, characterized in that: The conductive wire (11) satisfies: 50mm -1 <C:S<200mm -1 。 5. The electromagnetic induction heating coil according to claim 1, characterized in that: The conductive wires (11) can be spliced ​​together and can be infinitely expanded.

6. The electromagnetic induction heating coil according to claim 1, characterized in that: The cross-sectional shape of the conductive wire (11) is a random polygon or a tile family pattern.

7. The electromagnetic induction heating coil according to claim 1, characterized in that: The area of ​​the rectangular cross section is 1.5 mm 2 ~4.5mm 2 The number of the conductive wires (11) is 100 to 400.

8. A method for manufacturing an electromagnetic induction heating coil as claimed in any one of claims 1 to 7, characterized in that: The manufacturing method comprises the following steps: Step 1: Determine the coil cross-sectional area A1 based on the selected conductive wire material and the current carrying capacity of the aerosol generating device; Step 2: According to the material of the conductive wire and the operating frequency of the aerosol generating device, the diameter of the conductive wire is selected by calculating the skin depth, thereby determining the cross-sectional area A2 of the selected conductive wire; Step 3: Obtain the range of the number of strands of the selected conductive wire material by using the ratio of A1 and A2; Step 4: Gather the above number of conductive wires into a bundle; Step 5: tightly wrap the coating portion around the outer periphery of the conductive wire bundle to obtain the initial product of the electromagnetic induction heating coil; Step 6: Pressing the heating coil primary product into a rectangular outline raw material by a pressure device; Step 7: Wind the pressed raw material to obtain an electromagnetic induction heating coil.

9. The method for manufacturing an electromagnetic induction heating coil according to claim 8, characterized in that: The specific operation steps of step 4 are as follows: Step 41: spraying the selected conductive wires with a spray of a bonding material evenly to form a uniform bonding material coating on the surface of each conductive wire; Step 42: Arrange the conductive wires with the bonding material coating in parallel; or twist the conductive wires with the bonding material coating into multiple strands.

10. A method for manufacturing an electromagnetic induction heating coil as claimed in any one of claims 1 to 5, characterized in that: The manufacturing method comprises the following steps: Step 1: Determine the coil cross-sectional area A1 based on the selected conductive wire material and the current carrying capacity of the aerosol generating device; Step 2: According to the material of the conductive wire and the operating frequency of the aerosol generating device, the diameter of the conductive wire is selected by calculating the skin depth, thereby determining the cross-sectional area A2 of the selected conductive wire; Step 3: Obtaining the selected strand number range of the conductive wire material through the ratio of A1 and A2; Step 4: Processing the conductive wire to obtain a polygonal cross-section, wherein the polygons can be spliced ​​together to be infinitely expanded; Step 5: Arrange the conductive wires in parallel and connect them to form a bundle; Step 6: tightly wrap the coating portion around the outer periphery of the conductive wire bundle to obtain a preliminary electromagnetic induction heating coil; Step 7: Pressing the coil into a rectangular shape by a pressure device; Step 8: Winding the raw material into a shape to obtain an electromagnetic induction heating coil.

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