Electrothermal conversion-based direct heating device for tobacco products and manufacturing method therefor

Abstract

Provided are an electrothermal conversion-based direct heating device (1) for tobacco products (2) and a manufacturing method therefor. The heating device (1) comprises a heating component (11), a neck member (12), and a positioning seat (13) that are integrally formed; one end of a tobacco product (2) is inserted from an opening (121) of the neck member (12), and a through hole (113) passing through the heating component (11) extends into the positioning seat (13) and abuts against a step (131) in the positioning seat (13), so as to form an air exchange chamber (6); the other end of the tobacco product (2) extends out of the opening (121) to serve as a mouthpiece, and the tobacco product (2) is securely retained by means of the neck member (12) and is directly heated by means of an electrothermal conversion element (111). A tobacco segment (22) is directly heated in a surrounding configuration by means of the through hole (113) formed in the heating component (11), and a hollow cavity (114) can form an air heat insulation chamber together with thermal insulation cotton (15), such that the electrothermal conversion element (111) achieves low heat loss, fast temperature rise, high heating efficiency, precise heating of the tobacco segment (22), a large heating area, and uniform heating; a rapid heating effect can be achieved without requiring an excessively high heating temperature, so that the surface of the tobacco product (2) is prevented from scorching; and the flexible and adaptable structure allows for adaptation to different tobacco products (2), effectively solving the problem of lip burning.

Description

An electrothermal conversion direct heating device for tobacco products and its preparation method Technical Field

[0001] This application relates to the field of smoke-free technology, and in particular to an electrothermal conversion direct heating device for tobacco products and its preparation method. Background Technology

[0002] Currently, there are generally two methods for heating tobacco products in smoking devices. One method involves embedding a metal plate inside the tobacco shreds, which is then heated using electromagnetic induction technology. However, the metal plate is usually small, limiting the heating area of ​​the tobacco shreds and resulting in insufficient heating. Furthermore, this method only works with tobacco products containing the metal plate.

[0003] Another method involves placing the tobacco product inside a heat-conducting shell, with a heating material surrounding the shell. Heat is transferred to the shell via this material, which then heats the tobacco product indirectly. However, this method requires higher temperatures, results in greater heat loss from the heating material, slow heating of the tobacco product, inaccurate temperature control of the heating material, and a hot mouthpiece. Summary of the Invention

[0004] The purpose of this application is to provide an electrothermal conversion direct heating device for tobacco products and its preparation method, so as to solve the technical problems existing in the prior art, such as insufficient heating of tobacco, slow heating speed, hot mouthpiece, and high heat loss. The various technical effects of the optional technical solutions provided in this application are detailed below.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] This application provides an electrothermal conversion direct heating device for tobacco products, the electrothermal conversion direct heating device being configured to heat tobacco products to generate aerosol, the electrothermal conversion direct heating device comprising:

[0007] An integrally molded heating device includes an electrothermal conversion element and an injection molded part, which are combined by in-mold injection molding. The injection molded part is formed and fixes the electrothermal conversion element during the in-mold injection molding process. The inner surface of the injection molded part and the inner surface of the electrothermal conversion element are on the same curved surface, and a through hole is formed for accommodating the tobacco product. Both ends of the electrothermal conversion element are exposed on the outer surface of the injection molded part for connecting external conductive pins. The heating device has one or more hollow cavities for forming an air insulation chamber.

[0008] The neck component is a hollow structure, with one end of the neck component connected to one end of the injection molded part, and the other end of the neck component having an opening.

[0009] A positioning seat, one end of which is an open structure and the other end is a closed structure; the open structure at one end of the positioning seat is connected to the other end of the injection molded part; the inner bottom of the closed structure of the positioning seat has at least one step for limiting the tobacco product.

[0010] One end of the tobacco product is inserted through the opening of the neck piece, passes through the through hole into the positioning seat, and abuts against the step to form an air exchange chamber; the other end of the tobacco product extends out from the opening as a mouthpiece, the tobacco product is secured by the neck piece, and is directly heated by the electrothermal conversion element.

[0011] In some embodiments, heat insulation rings are placed at both ends of the heating device. The heat insulation rings are integrated with one end of the neck member and one end of the positioning seat opening structure to form a receiving cavity for placing the tobacco product, and the tobacco product extends out from the opening at the other end of the neck member.

[0012] In some embodiments, the electrothermal conversion element includes one or more spiral coils, the inner surface of the spiral coil and the inner surface of the injection molded part are on the same curved surface; the injection molded part is combined with the spiral coil by in-mold injection molding, the spiral coil is fixed after in-mold injection molding, a distance is maintained between two adjacent spiral coils, and the outer surface portion of the spiral coil is exposed in the hollow cavity formed by the injection molded part.

[0013] In some embodiments, the spiral coil is circular or raceway-shaped, so that the through hole is cylindrical or raceway-shaped.

[0014] In some embodiments, at least two grooves are provided between the inner surface of the through hole and the outer surface of the tobacco article, and the opening of the neck piece, the grooves and the ventilation chamber form an air circulation channel.

[0015] In some embodiments, the internal shape of the opening of the neck member matches the shape of the through hole, and the opening has at least two protrusions facing the center of the opening, so that the tobacco product can be deformed by the protrusions and form the groove when passing through the through hole.

[0016] In some embodiments, when the through hole is shaped like a racetrack cylinder hole, the length of the line connecting the two bends of the racetrack cylinder is greater than or equal to the cross-sectional diameter of the tobacco product, and the length of the line connecting the two straight sections of the racetrack cylinder is less than or equal to the cross-sectional diameter of the tobacco product.

[0017] In some embodiments, the electrothermal conversion direct heating device further includes thermal insulation cotton, which wraps the outer surface of the injection molded part, and the thermal insulation cotton and the hollow cavity form an air insulation chamber.

[0018] In some embodiments, a plurality of the hollow cavities are evenly distributed around the circumference of the injection molded part, the thermal insulation cotton wraps the outer surface of the injection molded part, and the hollow cavities and the thermal insulation cotton form an air insulation chamber.

[0019] Implementing one of the above-mentioned technical solutions of this application has the following advantages or beneficial effects: An electrothermal conversion direct heating device of this application includes a heating element, a neck component, and a positioning seat. The heating element is formed by in-mold injection molding of an electrothermal conversion element and an injection molded part. The formed through-hole surrounds the tobacco shreds of the tobacco product, directly and precisely heating the tobacco product. The heated area of ​​the tobacco product is large and uniform. Multiple hollow cavities on the outer surface of the heating element can form an air insulation chamber, resulting in less heat loss than indirect heating. This allows the tobacco shreds to heat up quickly and efficiently, achieving the heating effect without requiring excessively high temperatures, thus preventing the surface of the tobacco product from burning before the internal temperature of the tobacco shreds reaches the smoking point. Furthermore, one end of the tobacco product abuts against the closed end of the receiving cavity to form an air exchange chamber, which, combined with the opening, forms an air circulation channel. This reduces the resistance when smoking the tobacco product, and the other end of the tobacco product located at the opening serves as the mouthpiece, preventing burns. The tobacco product is secured by the neck component, preventing it from being pulled out of the through-hole when the user inhales through the mouthpiece. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0021] Figure 1 is a schematic diagram of the structure of the electrothermal conversion direct heating device involved in the embodiment of this application;

[0022] Figure 2 is a schematic diagram of the structure of the electrothermal conversion direct heating device according to the embodiment of this application after it is inserted into a tobacco product;

[0023] Figure 3 is an exploded view of Figure 2;

[0024] Figure 4 is a first structural diagram of the injection molded part involved in the embodiment of this application;

[0025] Figure 5 is a second structural diagram of the injection molded part involved in the embodiment of this application;

[0026] Figure 6 is a cross-sectional view of Figure 2;

[0027] Figure 7 is a schematic diagram of the structure of an electrothermal conversion element including multiple coils according to an embodiment of this application;

[0028] Figure 8 is another structural schematic diagram of the electrothermal conversion element involving multiple coils according to an embodiment of this application;

[0029] Figure 9 is a top view of the structure of the electrothermal conversion direct heating device involved in the embodiment of this application;

[0030] Figure 10 is a schematic flowchart of the preparation method of the electrothermal conversion direct heating device for tobacco products according to the embodiments of this application;

[0031] In the diagram: 1. Electrothermal conversion direct heating device; 2. Tobacco product; 3. Conductive pin; 5. Temperature sensor; 6. Ventilation chamber; 11. Heating device; 12. Neck part; 13. Positioning seat; 14. Heat insulation ring; 15. Insulation cotton; 21. First end sponge segment; 22. Tobacco shred segment; 23. Second end sponge segment; 51. Temperature sensor pin; 111. Electrothermal conversion element; 112. Injection molded part; 113. Through hole; 114. Hollow cavity; 115. Structural gap; 116. Diameter; 117. Helical coil; 118. Spacing; 119. Hollow channel; 121. Opening; 122. Protrusion; 131. Step. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, various exemplary embodiments described below will be referenced to the accompanying drawings, which form part of the exemplary embodiments and depict various exemplary embodiments that may be adopted to implement this application. Unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. It should be understood that they are merely examples of processes, methods, and apparatuses consistent with some aspects of this application disclosed as detailed in the appended claims, and other embodiments may be used, or structural and functional modifications may be made to the embodiments listed herein without departing from the scope and spirit of this application.

[0033] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," etc., indicate the orientation or positional relationship based on 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 referred element must have a specific orientation, or be constructed and operated in a specific orientation. The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. The term "multiple" means two or more. The terms "connected" and "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections, integral connections, mechanical connections, electrical connections, communication connections, direct connections, indirect connections through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. The term "and / or" includes any and all combinations of one or more of the related listed items. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] To illustrate the technical solutions described in this application, specific embodiments are provided below, showing only the parts related to the embodiments of this application.

[0035] As shown in Figures 1 to 6, this application provides an electrothermal conversion direct heating device 1 for tobacco products, which is configured to heat tobacco products 2 to generate aerosol. The electrothermal conversion direct heating device 1 includes a heating element 11, a neck member 12, and a positioning seat 13.

[0036] The heating device 11 includes an electrothermal conversion element 111 and an injection molded part 112. The heating device 11 is a combination of the electrothermal conversion element 111 and the injection molded part 112 through in-mold injection molding. The injection molded part 112 is formed and fixes the electrothermal conversion element 111 during the in-mold injection molding process. The inner surface of the injection molded part 112 is on the same curved surface as the inner surface of the electrothermal conversion element 111, and forms a through hole 113 for accommodating the tobacco product 2. Both ends of the electrothermal conversion element 111 are exposed on the outer surface of the injection molded part 112 for connecting external conductive pins 3. The heating device 11 has one or more hollow cavities 114 for forming an air insulation chamber.

[0037] The injection molded part 112 can be made of a high-temperature resistant material with low thermal conductivity, such as PEEK or PI. The inner surface of the injection molded part 112 and the inner surface of the electrothermal conversion element 111 are on the same curved surface. The injection molded part 112 tightly fixes the electrothermal conversion element 111, and there is no discontinuity between the inner surfaces of the injection molded part 112 and the electrothermal conversion element 111. This ensures that the inner surface of the formed through hole 113 is smooth, guaranteeing smooth insertion of the tobacco product 2 into the through hole 113 and preventing displacement of the electrothermal conversion element 111. When the tobacco shreds 22 of the tobacco product 2 are heated to generate aerosol, potentially producing tar, the smooth inner surface of the through hole 113 facilitates cleaning. Furthermore, multiple hollow cavities 114 are formed on the outer surface of the injection molded part 112 during in-mold injection molding to expose portions of the electrothermal conversion element 111.

[0038] The neck part 12 is a hollow structure. One end of the neck part 12 is connected to one end of the injection molded part 112, and the other end of the neck part 12 is provided with an opening 121.

[0039] Specifically, the shape of the opening 121 at the other end of the neck part 12 matches the shape of the through hole 113. One end of the neck part 12 is connected to one end of the injection molded part 112, and the end faces of the neck part 12 and the heating device 11 do not contact each other. Furthermore, heat insulation rings 14 are placed at both ends of the heating device 11. The heat insulation rings 14 are integrated with one end of the neck part 12, as shown in Figure 3. The joint surface between one end of the neck part 12 and the injection molded part 112 forms a structural gap 115, which is connected by the interference fit formed between the diameter 116 of the outer surface of the heating device 11 and the neck part 12. By adopting this partial contact interference fit connection method, the contact area between the heating device 11 and the neck part 12 is effectively reduced, and the purpose is to prevent the heat of the heating device 11 from being conducted to the neck part 12.

[0040] The neck component 12 has three functions: first, it secures the tobacco product 2; specifically, at least two protrusions 122 are provided at the center of the opening 121 to secure the tobacco product 2. Simultaneously, when the tobacco product 2 is inserted, it is deformed by the protrusions 122, forming a groove in the through hole 113 for air circulation; second, the inserted portion of the tobacco product 2 is compressed by the opening 121, and after the overall deformation of the tobacco product 2, it matches the shape of the hollow channel 119 of the electrothermal conversion element 111, allowing for a tighter fit; third, it has a heat dissipation function. The material of component 12 can be plastic or a metal with good thermal conductivity, such as aluminum. Combined with the heat insulation effect of the heat insulation ring 14, when a portion of the tobacco product 2 requires a high temperature, the second end sponge segment 23 is heated due to heat conduction, causing it to scald the mouth. To prevent scalding during inhalation, a metal material is used to dissipate heat from the second end sponge segment 23. Simultaneously, when air circulates through the opening 121, the groove on the surface of the tobacco product 2, and the ventilation chamber 6, the heat from the surface of the sponge segment 23 near the opening 121 is carried into the ventilation chamber 6, effectively reducing the surface temperature of the second end sponge segment 23. This helps solve the problem of scalding the mouth and also reduces the user's inhalation resistance. When the user removes the tobacco product 2, the user pinches the second end sponge segment 23 exposed at the opening 121 and pulls it outward, thereby removing the tobacco product 2 from the receiving cavity.

[0041] The positioning seat 13 has an open structure at one end and a closed structure at the other end; the open structure at one end of the positioning seat 13 is connected to the other end of the injection molded part 112; the inner bottom of the closed structure of the positioning seat 13 has at least one step 131 for limiting the tobacco product 2. As shown in Figure 4, similar to the connection between the neck piece 12 and the heating device 11, the heat insulation ring 14 is integrated with one end of the opening structure of the positioning seat 13. That is, the heat insulation rings 14 at both ends of the heating device 11 are integrated with one end of the neck piece 12 and one end of the opening structure of the positioning seat 13, respectively, so that the end faces of the positioning seat 13 and the heating device 11 do not contact each other. A structural gap 115 is formed on the joint surface between the opening structure of the positioning seat 13 and the injection molded part 112. The connection is made by the interference fit formed between the diameter 116 of the outer surface of the heating device 11 and the positioning seat 13. This partial contact interference fit connection method reduces the contact area between the heating device 11 and the positioning seat 13. The purpose is to prevent the heat of the heating device 11 from being conducted to the positioning seat 13. The inner bottom of the closed structure of the positioning seat 13 has at least one step 131 for limiting the tobacco product 2. When one end of the tobacco product 2 abuts against the step 131, it forms a ventilation chamber 6 with the inner bottom of the positioning seat 13.

[0042] Specifically, the heating device 11, neck piece 12, and positioning seat 13, which are equipped with conductive pins 3, are connected together by a partial contact interference fit to form a receiving cavity for accommodating the tobacco product 2. One end of the tobacco product 2 passes through the through hole 113 from the opening 121 of the neck piece 12 and abuts against the inner step 131 of the positioning seat 13. The tobacco product 2 and the bottom of the positioning seat 13 form an air exchange chamber 6. The tobacco shreds of the tobacco product 2 are surrounded by the through hole 113. The other end of the tobacco product 2 is fixed by the neck piece 12 and extends out from the opening 121 of the neck piece 12 as a mouthpiece, and is directly heated by the electrothermal conversion element 111.

[0043] In some embodiments, the tobacco product 2 is as shown in Figure 3. The tobacco product 2 is cylindrical with a length of 45mm and includes three parts: a first end sponge segment 21, a middle tobacco shred segment 22, and a second end sponge segment 23. For example, the length of the first end sponge segment 21 is 5mm, the length of the middle tobacco shred segment 22 is 12mm, and the length of the second end sponge segment 23 is 28mm.

[0044] To match the tobacco product 2, the length of the hollow channel (119 in Figure 7 or Figure 8) formed by the electrothermal conversion element 111 itself is within 6-12mm. The length of the through hole 113 formed by the electrothermal conversion element 111 and the injection molded part 112 can be 8mm-14mm. The height of the ventilation chamber 6 is less than 2mm. The internal length of the cavity for accommodating the tobacco product 2 formed by the heating device 11, the neck part 12 and the positioning seat 13 is 13-25mm. Under the action of external force, the tobacco product 2 is partially inserted into the cavity for accommodating the tobacco product 2. At this time, the tobacco section 22 of the tobacco product 2 is just surrounded and wrapped by the electrothermal conversion element 111. The first end sponge section 21 and the middle tobacco section 22 are completely accommodated in the cavity. Most of the second end sponge section 23 is not in the cavity. The more the second end sponge section 23 protrudes, the better it is to reduce the burning sensation of the mouth.

[0045] After the tobacco product 2 is heated within the receiving cavity, it generates an aerosol, which is drawn out by the extended second-end sponge segment 23. Further, air enters the ventilation chamber 6 through the opening 121 of the neck piece 12, then enters through the first-end sponge segment 21, passes through the intermediate tobacco section 22, and is drawn out through the second-end sponge segment 23. Even if the tobacco section 22 generates e-liquid during heating, the e-liquid cannot be absorbed by the first-end sponge segment 21 and will fall directly into the positioning seat 13 without overflowing, making it easy to clean.

[0046] In some embodiments, the electrothermal conversion element 111 includes one or more spiral coils 117. The spiral coil 117 can be circular or raceway-shaped. The inner surface of the spiral coil 117 is on the same curved surface as the inner surface of the injection molded part 112. The injection molded part 112 is combined with the spiral coil 117 by in-mold injection molding. The spiral coil 117 is fixed during the in-mold injection molding process. A distance 118 is maintained between two adjacent spiral coils 117 to ensure that the spiral coils 117 do not contact each other. The outer surface portion of the spiral coil 117 is exposed in the hollow cavity 114 formed by the injection molded part 112.

[0047] The spiral coil 117 can be circular or raceway-shaped. The through hole 113 formed by the spiral coil 117 during the in-mold injection molding process is cylindrical or raceway-shaped. The through hole 113 is used to surround the tobacco product 2. The position of the electrothermal conversion element 111 formed by the spiral coil 117 is precisely surrounded by the tobacco section 22. The inner surface of the through hole 113 is in contact with or in most contact with the outer surface of the tobacco product 2.

[0048] The electrothermal conversion element 111 can be made of an alloy of at least two of the following: nickel, chromium, iron, copper, molybdenum, manganese, silver, silicon, antimony, sulfur, and phosphorus, and has a temperature coefficient.

[0049] In some embodiments, laser welding can be used to connect the two ends of the electrothermal conversion element 111 exposed on the outer surface of the injection molded part 112 on the heating device 11 to the conductive pin 3. The conductive pin 3 is electrically connected to the main control module of the smoking device. The main control module of the smoking device can directly obtain the resistance value of the electrothermal conversion element 111, thereby obtaining the temperature change of the electrothermal conversion element 111. If the main control module of the smoking device detects the temperature change of the electrothermal conversion element 111 through the temperature sensor 5, then the temperature sensor 5 is placed on the outer surface of the electrothermal conversion element 111 and fixed with high-temperature resistant adhesive tape. The temperature sensor 5 is used to obtain the temperature change of the electrothermal conversion element 111. The pin 51 of the temperature sensor 5 can be electrically connected to the main control module. The main control module obtains the temperature change of the electrothermal conversion element 111 through the temperature sensor 5.

[0050] In some embodiments, the inner surface of the through hole 113 has at least two grooves between the inner surface of the tobacco product 2 and the outer surface of the through hole 113, and the opening 121 of the neck piece 12, the grooves and the ventilation chamber 6 form an air circulation channel.

[0051] In some embodiments, the internal shape of the opening 121 of the neck member 12 matches the shape of the through hole 113, and at least two protrusions 122 are provided at the center of the opening 121. The tobacco product 2 can be deformed by being squeezed by the protrusions 122, forming a groove when passing through the through hole 113. The protrusions 122 are also used to clamp the tobacco product 2.

[0052] As shown in Figure 7, two adjacent spiral coils 117 are separated by an injection molded part 112. The spacing 118 between adjacent spiral coils 117 and the inner surface of the through hole 113 are on the same curved surface, making it easy for the tobacco product 2 to be penetrated through the through hole 113.

[0053] As shown in Figure 7, the spacing 118 between adjacent spiral coils 117 can be 0-0.8mm, the number of spiral coils 117 can be one or more turns, the cross-sectional width of the spiral coil 117 is 0.5mm-30mm, and the thickness is 0.05mm-10mm. The spiral coil 117 forms a hollow channel 119 by winding, and the inner surface of the hollow channel 119 is on the same curved surface as the inner surface of the injection molded part 112.

[0054] In some embodiments, the spiral coil 117 is circular or raceway-shaped, so that the through hole 113 is cylindrical or raceway-shaped.

[0055] As shown in Figure 7, if the spiral coil 117 is circular, the resulting hollow channel 119 is a cylindrical hole, and the through hole 113 formed by the injection molded part 112 and the spiral coil 117 is also a cylindrical hole; correspondingly, as shown in Figure 8, if the spiral coil 117 is circular, the resulting hollow channel 119 is a cylindrical hole, and the through hole 113 formed by the injection molded part 112 and the spiral coil 117 is also a cylindrical hole.

[0056] In some embodiments, when the through hole 113 is shaped like a racetrack cylindrical hole, the length of the line connecting the two bends of the racetrack cylindrical hole is greater than or equal to the cross-sectional diameter of the tobacco product 2, and the length of the line connecting the two straight sections of the racetrack cylindrical hole is less than or equal to the cross-sectional diameter of the tobacco product 2. This allows the outer surface of the tobacco product 2 to partially or completely contact the inner surface of the through hole 113, so the formed groove is actually the portion where the outer surface of the tobacco product 2 does not contact the inner surface of the through hole 113.

[0057] The working principle of the electrothermal conversion direct heating device 1 of this application is as follows: When the user smokes using the electrothermal conversion direct heating device 1, the first end sponge segment 21 of the tobacco product 2 is first inserted into the opening 121 of the electrothermal conversion direct heating device 1. The user holds the second end sponge segment 23 and pushes the tobacco product 2 so that it enters the receiving cavity formed by the electrothermal conversion direct heating device 11 to receive the tobacco product 2. When the tobacco product 2 abuts against the step 131 at the closed end of the receiving cavity, the tobacco product 2 is placed. The second end sponge segment 23 that has not entered the receiving cavity serves as the user's mouthpiece. At this time, the middle tobacco shred segment 22 is just around the through hole 113 where the electrothermal conversion element 111 of the electrothermal conversion direct heating device 1 is located. At this time, the tobacco product 2 is deformed after being squeezed by the opening 121 and the protrusion 122, so that the outer surface of the tobacco shred segment is in close contact with most of the inner surface of the through hole 113, and the multiple grooves formed on the outer surface of the tobacco product 2 are not in contact with the inner surface of the through hole 113.

[0058] Then, the user presses the switch of the electrothermal conversion direct heating device 1 to start the electrical connection between the electrothermal conversion direct heating device 1 and the main control module of the external smoking device. The electrothermal conversion element 111 starts to heat up and directly heats the middle tobacco section 22. At the same time, the main control module of the smoking device detects the temperature change of the electrothermal conversion element 111 in real time.

[0059] After the middle tobacco section 22 is heated to the preset time, the main control module of the smoking device detects that the temperature of the electrothermal conversion element 111 has reached the preset temperature value, and prompts the user to smoke. At this time, the user sucks into the second end sponge section 23, which serves as the mouthpiece. At this time, because the protrusion 122 at the opening 121 fixes the second end sponge segment 23, the tobacco product 2 will not be carried out of the receiving cavity during inhalation. Furthermore, due to the closed structure at one end of the receiving cavity, the first end sponge segment 21 abuts against the closed end step 131 of the receiving cavity to form a ventilation chamber 6. During inhalation, as indicated by the arrow in Figure 6, air flows from the opening 121 along the groove formed by the protrusion 122 squeezing the tobacco product 2 into the ventilation chamber 6. The air in the ventilation chamber 6 passes through the first end sponge segment 21 and the middle tobacco segment 22 and is drawn out from the second end sponge segment 23 under the action of suction. The air is heated during the process of entering the ventilation chamber 6 from the opening 121. The air in the ventilation chamber 6 is always preheated, which can ensure that the internal temperature change of the middle tobacco segment 22 is small. At the same time, when the air enters from the opening 121, the heat on the surface of the second end sponge segment 23 near the opening 121 is carried into the ventilation chamber 6, effectively reducing the surface temperature of the second sponge segment 23. It helps solve the problem of burning the mouth, while also reducing the suction resistance for users.

[0060] In some embodiments, as shown in FIG9, at least one step 131 extends out from one end of the closed structure of the receiving cavity. The cross section of the step 131 is much smaller than the cross section of the tobacco product 2, so that when the tobacco product 2 is inserted into the receiving cavity, the first end sponge segment 21 comes into contact with the step 131 when it comes into contact with the receiving cavity. At this time, the first end sponge segment 21 and the bottom of the receiving cavity form an air exchange chamber 6 to facilitate air circulation.

[0061] In some embodiments, the electrothermal conversion direct heating device 1 also includes insulation cotton 15, which wraps the outer surface of the injection molded part 112.

[0062] The insulation cotton 15 is a heat insulation layer, which can be made of heat insulation cotton or heat insulation cotton. It is wrapped around the outer surface of the injection molded part 112. At this time, the hollow cavity 114 on the outer surface of the injection molded part 112 and the insulation cotton 15 form an air heat insulation chamber, which effectively prevents the heat of the heating device 11 from escaping to its outer surface, and provides heat insulation for the heating device 11 to minimize heat loss.

[0063] In some embodiments, a plurality of hollow cavities 114 are evenly distributed around the injection molded part 112, and the insulation cotton 15 wraps the outer surface of the injection molded part 112, forming an air insulation chamber with the hollow cavities 114 and the insulation cotton 15.

[0064] As shown in Figure 5, multiple hollow cavities 114 are evenly distributed around the injection molded part 112, exposing part of the spiral coil 117. After the outer surface of the injection molded part 112 is wrapped with heat insulation cotton 15, the heat of the spiral coil 117 can be evenly distributed in the injection molded part 112 through the wrapping of heat insulation cotton 15 because the multiple hollow cavities 114 expose part of the spiral coil 117. The heat is not easily dissipated, and the tobacco product 2 is heated more evenly in the cavity.

[0065] The electrothermal conversion direct heating device 1 of this application embodiment includes a heating element 11, a neck part 12, and a positioning seat 13. The heating element 11 is formed by in-mold injection molding of the electrothermal conversion element 111 and the injection molded part 112. The formed through hole 113 surrounds the tobacco shreds of the tobacco product 2, directly and precisely heating the tobacco product 2. The heated area of ​​the tobacco product 2 is large and uniform. Multiple hollow cavities 114 on the outer surface of the heating element 11 and the heat insulation cotton 15 form an air insulation chamber, which has less heat loss than indirect heating, resulting in a faster heating rate of the tobacco shreds and higher heating efficiency. The heating effect can be achieved without excessively high temperatures, avoiding the surface of the tobacco product 2 from burning while the internal temperature of the tobacco shreds is not yet at the smoking temperature; furthermore, one end of the tobacco product 2 abuts against the closed end of the receiving cavity to form an air exchange chamber 6, which, together with the opening 121, forms an air circulation channel, making the resistance to smoking the tobacco product 2 low, and the other end of the tobacco product 2 located at the opening 121 serves as a mouthpiece that will not burn the mouth, and the tobacco product 2 is fixed by the neck piece 12, so that the tobacco product 2 will not be pulled out of the through hole 113 when the user smokes the mouthpiece.

[0066] As shown in Figure 10, this application also provides a method for preparing an electrothermal conversion direct heating device for tobacco products, including steps S10 to S70.

[0067] S10. Select alloy plate material and manufacture it into an electrothermal conversion element with the inner surface on the same curved surface.

[0068] As shown in Figures 7 and 8, the electrothermal conversion element 111 includes one or more spiral coils 117.

[0069] Therefore, in some embodiments, step S10 may include:

[0070] Select strip-shaped plates made of alloy material;

[0071] The strip material is wound according to a preset shape, a preset number of turns, and a spacing of 118 to form a spiral coil with a spacing of one or more turns, and the inner surfaces of the spiral coil are on the same curved surface.

[0072] Specifically, the alloy material may include at least two of nickel, chromium, iron, copper, molybdenum, manganese, silver, silicon, antimony, niobium, sulfur, and phosphorus, or any one of nickel-chromium alloy, iron-chromium-aluminum alloy, nickel-copper alloy, and stainless steel alloy, and has a temperature coefficient. The cross-sectional width of the strip plate can be 0.5mm-30mm, the thickness can be 0.05mm-10mm, the number of turns can be 1-8, and the spacing 118 between each turn can be 0-0.8mm. The strip plate can be wound into a circular or racetrack-shaped spiral coil 117 with 1-8 turns according to the preset number of turns and spacing.

[0073] In some implementations, step S10 may include:

[0074] Select a tubular plate of a preset size;

[0075] The tubular plate is laser-cut according to a preset number of turns to form a spiral coil 117 with a preset spacing of 118 turns or more, and the inner surfaces of the spiral coil 117 are on the same curved surface.

[0076] Specifically, the pre-sized tubular plate can be a tubular plate with an inner diameter of 7.4mm, an outer diameter of 7.8mm, and a length of 8mm. The shape of the tubular plate can be a cylinder or a running track cylinder. The pre-set number of laps can also be 1-8 laps, and the pre-set spacing can be 0-0.8mm.

[0077] As shown in Figures 7 and 8, the spiral coil 117 formed by winding or laser cutting is circular or raceway-shaped, and the inner surface of the spiral coil 117 is cylindrical or raceway-shaped. The spacing 118 between adjacent spiral coils 117 can be 0-0.8 mm. The number of spiral coils 117 can be one or more turns, such as five turns. The cross-sectional width of the spiral coil 117 is 0.5 mm-30 mm, and the thickness is 0.05 mm-10 mm. The spiral coil 117 forms a hollow channel 119, which is cylindrical or raceway-shaped.

[0078] S20. Make the first mold corresponding to the heating element, the second mold corresponding to the neck part, and the third mold corresponding to the positioning seat.

[0079] S30. Fix the electrothermal conversion element in the cavity of the first mold, and fill the cavity of the first mold with plastic by injection molding machine so that the electrothermal conversion element and the plastic are combined in the cavity of the first mold to form a hollow heating device. The injection molded part is formed during the injection molding process and forms multiple hollow cavities to expose part of the outer surface of the electrothermal conversion element. The obtained heating device is taken out from the cavity of the first mold.

[0080] Specifically, as shown in Figures 3 and 4, the heating device 11 includes an electrothermal conversion element 111 and an injection molded part 112. The injection molded part 112 is directly injection molded in the cavity of the first mold. The heating device 11 is a combination of the electrothermal conversion element 111 and the injection molded part 112 injection molded in the mold. The injection molded part 112 is formed and fixes the electrothermal conversion element 111 during the in-mold injection process. The inner surface of the injection molded part 112 is on the same curved surface as the inner surface of the electrothermal conversion element 111, and forms a through hole 113 for accommodating the tobacco product 2. The two ends of the electrothermal conversion element 111 are exposed on the outer surface of the injection molded part 112 for connecting external conductive pins 3. The heating device 11 has one or more hollow cavities 114 for forming an air insulation chamber.

[0081] The injection molded part 112 can be made of a high-temperature resistant material with low thermal conductivity, such as PEEK or PI. The inner surface of the injection molded part 112 and the inner surface of the electrothermal conversion element 111 are on the same curved surface. The injection molded part 112 tightly fixes the electrothermal conversion element 111, and there is no discontinuity between the inner surfaces of the injection molded part 112 and the electrothermal conversion element 111. This ensures that the inner surface of the formed through hole 113 is smooth, guaranteeing smooth insertion of the tobacco product 2 into the through hole 113 and preventing displacement of the electrothermal conversion element 111. When the tobacco shreds 22 of the tobacco product 2 are heated to generate aerosol, potentially producing tar, the smooth inner surface of the through hole 113 facilitates cleaning. Furthermore, multiple hollow cavities 114 are formed on the outer surface of the injection molded part 112 during in-mold injection molding to expose portions of the electrothermal conversion element 111.

[0082] In some embodiments, when the through hole 113 of the hollow structure of the heating device formed after the electrothermal conversion element 111 and the plastic are injection molded in the cavity of the first mold is shaped like a racetrack cylindrical hole, the length of the line connecting the two bends of the racetrack cylindrical hole is greater than or equal to the cross-sectional diameter of the tobacco product 2, and the length of the line connecting the two straight sections of the racetrack cylindrical hole is less than or equal to the cross-sectional diameter of the tobacco product 2.

[0083] This allows the outer surface of the tobacco product 2 to partially or completely contact the inner surface of the through hole 113, so the groove formed is actually the part where the outer surface of the tobacco product 2 does not contact the inner surface of the through hole 113.

[0084] In some embodiments, after step S30, the preparation method further includes:

[0085] Heat insulation rings 14 are placed at both ends of the injection molded part 112.

[0086] The heat insulation ring 14 is used to reduce the heat transfer from the heating element 11 to the neck part 12 and the positioning seat 13. Therefore, the heat insulation ring 14 can also be placed after step S50 and / or S60, as long as the heat insulation ring 14 is placed at both ends of the injection molded part before step S70.

[0087] S40. Weld conductive pins to both ends of the electrothermal conversion element exposed on the outer surface of the injection molded part.

[0088] In some embodiments, laser welding can be used to connect the two ends of the electrothermal conversion element 111 exposed on the outer surface of the injection molded part 112 on the heating device 11 to the conductive pins 3. The conductive pins 3 can be electrically connected to the main control module of the smoking device, and the main control module of the smoking device can directly obtain the resistance value of the electrothermal conversion element 111, thereby obtaining the temperature change of the electrothermal conversion element 111.

[0089] In some embodiments, if the main control module of the smoking device detects the temperature change of the electrothermal conversion element 111 via the temperature sensor 5, then after step S40, the preparation method may further include:

[0090] The temperature sensor 5 is attached to the outer surface of the electrothermal conversion element 111, and the pin 51 of the temperature sensor 5 extends out from the outer surface of the injection molded part 112.

[0091] Specifically, as shown in Figure 3, the temperature sensor 5 is placed on the outer surface of the electrothermal conversion element 111 and fixed with high-temperature resistant adhesive tape. The temperature sensor 5 is used to obtain the temperature change of the electrothermal conversion element 111. The pin 51 of the temperature sensor 5 can be electrically connected to the main control module of the smoking device. The main control module obtains the temperature change of the electrothermal conversion element 111 through the temperature sensor 5.

[0092] In some embodiments, after step S40, the preparation method further includes:

[0093] Insulating cotton 15 is wrapped around the outer surface of the injection molded part 112 to cover the hollow cavity 114 and the temperature sensor 5.

[0094] Specifically, as shown in Figures 5 and 1, the insulation cotton 15 is a heat insulation layer, which can be made of heat insulation cotton or heat insulation cotton material and wrapped around the outer surface of the injection molded part 112. At this time, the hollow cavity 114 on the outer surface of the injection molded part 112 and the insulation cotton 15 form an air heat insulation chamber, which effectively prevents the heat of the heating device 11 from escaping to its outer surface, and provides heat insulation for the heating device 11 to minimize heat loss.

[0095] In some embodiments, a plurality of hollow cavities 114 are evenly distributed around the injection molded part 112, and the insulation cotton 15 wraps the outer surface of the injection molded part 112, forming an air insulation chamber with the hollow cavities 114 and the insulation cotton 15.

[0096] As shown in Figure 5, multiple hollow cavities 114 are evenly distributed around the injection molded part 112, exposing part of the spiral coil 117. After the outer surface of the injection molded part 112 is wrapped with heat insulation cotton 15, multiple air insulation chambers are formed. Since the multiple hollow cavities 114 expose part of the spiral coil 117, the heat of the spiral coil 117 can be retained in the air insulation chamber through the wrapping of heat insulation cotton 15, and the heat is not easily dissipated. This makes the tobacco product 2 more evenly heated in the cavity.

[0097] S50. Fill the cavity of the second mold with injection molding material using an injection molding machine. The neck part is formed into a hollow structure during the injection molding process. Remove the obtained neck part from the cavity of the second mold, or process the sheet metal by machining to obtain a hollow neck part.

[0098] The neck component 12 can be injection molded to obtain a plastic material; or it can be machined from sheet metal. Machining methods can include CNC machining, lathe machining, and milling machine machining. CNC machining usually refers to computer-controlled precision machining. The sheet metal can be a metal material with good thermal conductivity, such as an aluminum block. In this case, the material of the machined neck component 12 will be aluminum, which has a heat dissipation effect.

[0099] The obtained neck component 12, as shown in Figures 1 and 3 to 5, has a hollow structure. One end of the neck component 12 is used to connect to one end of the injection molded part 112, and the other end of the neck component 12 has an opening 121. Specifically, the shape of the opening 121 at the other end of the neck component 12 matches the shape of the through hole 113. One end of the neck component 12 is used to connect to one end of the injection molded part 112, and the end faces of the neck component 12 and the heating device 11 do not contact each other.

[0100] The neck piece 12 has three functions: first, it secures the tobacco product 2; specifically, at least two protrusions 122 are provided at the center of the opening 121 to secure the tobacco product 2. Simultaneously, when the tobacco product 2 is inserted, it is deformed by the protrusions 122, forming a groove in the through hole 113 for air circulation; second, the inserted part of the tobacco product 2 is compressed by the opening 121, and after the tobacco product 2 deforms as a whole, it matches the shape of the hollow channel 119 of the electrothermal conversion element 111, allowing for a tighter fit; third, it connects with the heat insulation ring 14. The neck piece 12 is made of a metal with good thermal conductivity, such as aluminum. When a portion of the tobacco product 2 requires a high temperature, the second-end sponge segment 23 can be heated due to heat conduction, causing burns to the mouth. To prevent burns during inhalation, a metal material is used to dissipate heat from the second-end sponge segment 23. Simultaneously, when air circulates through the opening 121, the grooves on the surface of the tobacco product 2, and the ventilation chamber 6, heat from the surface of the sponge segment 23 near the opening 121 is carried into the ventilation chamber 6, effectively reducing the surface temperature of the second-end sponge segment 23. This helps solve the burn problem and also reduces suction resistance for the user. When the user removes the tobacco product 2, they squeeze the second-end sponge segment 23 exposed at the opening 121 and pull it outwards, thus removing the tobacco product 2 from the receiving cavity.

[0101] In some embodiments, the inner surface of the through hole 113 has at least two grooves between the inner surface of the tobacco product 2 and the outer surface of the through hole 113, and the opening 121 of the neck piece 12, the grooves and the ventilation chamber 6 form an air circulation channel.

[0102] In some embodiments, the internal shape of the opening 121 of the neck member 12 matches the shape of the through hole 113, and at least two protrusions 122 are provided at the center of the opening 121. The tobacco product 2 can be deformed by being squeezed by the protrusions 122, forming a groove when passing through the through hole 113. The protrusions 122 are also used to clamp the tobacco product 2.

[0103] S60. Plastic is filled into the cavity of the third mold by an injection molding machine. The positioning seat is formed into an open structure at one end and a closed structure at the other end during the injection molding process, and at least one step is formed at the bottom of the closed structure. The obtained positioning seat is removed from the cavity of the third mold.

[0104] As shown in Figure 3, the positioning seat 13 obtained by injection molding has an open structure at one end and a closed structure at the other end; the open structure at one end of the positioning seat 13 is connected to the other end of the injection molded part 112; as shown in Figure 9, the inner bottom of the closed structure of the positioning seat 13 has at least one step 131 for limiting the tobacco product 2.

[0105] In some embodiments, the cross-section of the step 131 is much smaller than the cross-section of the tobacco product 2, so that when the tobacco product 2 is inserted into the receiving cavity, the first end sponge segment 21 comes into contact with the step 131 when it comes into contact with the receiving cavity. At this time, the first end sponge segment 21 and the bottom of the receiving cavity form an air exchange chamber 6 to facilitate air circulation.

[0106] S70. Fix the neck piece to one end of the injection molded part, and fix one end of the opening structure of the positioning seat to the other end of the injection molded part to obtain an electrothermal conversion direct heating device.

[0107] In some implementations, step S70 may include:

[0108] After placing the heat insulation ring at one end of the injection molded part, a portion of one end of the injection molded part is inserted into the hollow structure of the neck member, and an interference fit is used to fix one end of the injection molded part to the neck member; after placing the heat insulation ring at the other end of the injection molded part, a portion of the other end of the injection molded part is inserted into one end of the positioning seat opening structure, and an interference fit is used to fix the other end of the injection molded part to one end of the positioning seat opening structure.

[0109] Specifically, as shown in Figure 6, heat insulation rings 14 are placed at both ends of the heating device 11. After the heat insulation rings 14 are placed, one end of the injection molded part 112 is partially inserted into one end of the neck part 12 to form an interference fit and become a whole. The joint surface between the injection molded part 112 and the neck part 12 forms a structural gap 115, which is connected by the interference fit formed by the diameter 116 of the outer surface of the heating device 11 and the neck part 12. By adopting this partial contact interference fit connection method, the contact area between the heating device 11 and the neck part 12 is effectively reduced, and the purpose is to prevent the heat of the heating device 11 from being conducted to the neck part 12.

[0110] As shown in Figure 6, similar to the connection between the neck piece 12 and the heating element 11, after placing the heat insulation ring 14, the other end of the heating element 11 (i.e., the other end of the injection molded part 112) is partially inserted into one end of the opening structure of the positioning seat 13, forming an interference fit to form a whole. That is, the heat insulation rings 14 at both ends of the heating element 11 are respectively integrated with one end of the neck piece 12 and one end of the opening structure of the positioning seat 13, so that the end faces of the positioning seat 13 and the heating element 11 do not contact each other, and the mating surface between the opening structure of the positioning seat 13 and the injection molded part 112... Structurally, a structural gap 115 is formed, which is connected by the interference fit formed by the diameter 116 of the outer surface of the heating device 11 and the positioning seat 13. This partial contact interference fit connection method reduces the contact area between the heating device 11 and the positioning seat 13, so as to prevent the heat of the heating device 11 from being conducted to the positioning seat 13. The inner bottom of the closed structure of the positioning seat 13 has at least one step 131 for limiting the tobacco product 2. When one end of the tobacco product 2 abuts against the step 131, it forms an air exchange chamber 6 with the inner bottom of the positioning seat 13.

[0111] The electrothermal conversion direct heating device 1 prepared by the method of this application for preparing an electrothermal conversion direct heating device for tobacco products forms a receiving cavity for accommodating tobacco product 2. One end of tobacco product 2 passes through a through hole 113 from the opening 121 of the neck member 12 and abuts against the inner step 131 of the positioning seat 13. The tobacco product 2 and the bottom of the positioning seat 13 form an air exchange chamber 6. The tobacco shreds of tobacco product 2 are surrounded by the through hole 113. The other end of tobacco product 2 is fixed by the neck member 12 and extends out from the opening 121 of the neck member 12 as a mouthpiece, and is directly heated by the electrothermal conversion element 111.

[0112] In some embodiments, the tobacco product 2 is as shown in FIG8. The tobacco product 2 is cylindrical with a length of 45mm and includes three parts: a first end sponge segment 21, a middle tobacco shred segment 22 and a second end sponge segment 23. For example, the length of the first end sponge segment 21 is 5mm, the length of the middle tobacco shred segment 22 is 12mm, and the length of the second end sponge segment 23 is 28mm.

[0113] To match the tobacco product 2, the length of the hollow channel (119 in Figure 7 or Figure 8) formed by the electrothermal conversion element 111 itself is within 6-12mm. The length of the through hole 113 formed by the electrothermal conversion element 111 and the injection molded part 112 can be 8mm-14mm. The height of the ventilation chamber 6 is less than 2mm. The internal length of the receiving cavity for accommodating the tobacco product 2 formed by the heating device 11, the neck part 12 and the positioning seat 13 is 13mm-25mm. Under the action of external force, the tobacco product 2 is partially inserted into the receiving cavity, so that the tobacco section 22 of the tobacco product 2 is just surrounded and wrapped by the electrothermal conversion element 111. The first end sponge section 21 and the middle tobacco section 22 are completely contained in the receiving cavity, while most of the second end sponge section 23 is not contained in the receiving cavity. The more the second end sponge section 23 protrudes, the better it is to reduce the burning sensation of the mouth.

[0114] After the tobacco product 2 is heated within the receiving cavity, it generates an aerosol, which is drawn out by the extended second-end sponge segment 23. Further, air enters the ventilation chamber 6 through the opening 121 of the neck piece 12, then enters through the first-end sponge segment 21, passes through the intermediate tobacco section 22, and is drawn out through the second-end sponge segment 23. Even if the tobacco section 22 generates e-liquid during heating, the e-liquid cannot be absorbed by the first-end sponge segment 21 and will fall directly into the positioning seat 13 without overflowing, making it easy to clean.

[0115] The working principle of the electrothermal conversion direct heating device 1 prepared by the method of this application for preparing an electrothermal conversion direct heating device for tobacco products is as follows: When the user smokes using the electrothermal conversion direct heating device 1, the first end sponge segment 21 of the tobacco product 2 is first inserted into the opening 121 of the electrothermal conversion direct heating device 1. The user holds the second end sponge segment 23 and pushes the tobacco product 2 so that the tobacco product 2 enters the receiving cavity formed by the electrothermal conversion direct heating device 11 to receive the tobacco product 2. When the tobacco product 2 abuts against the step 131 at the closed end of the receiving cavity, the tobacco product 2 is placed. The second end sponge segment 23 that has not entered the receiving cavity serves as the user's mouthpiece. At this time, the middle tobacco shred segment 22 is just around the through hole 113 where the electrothermal conversion element 111 of the electrothermal conversion direct heating device 1 is located. At this time, due to the deformation caused by the tobacco product 2 being squeezed by the opening 121 and the protrusion 122, the outer surface of the tobacco shred segment is in close contact with most of the inner surface of the through hole 113, and the multiple grooves formed on the outer surface of the tobacco product 2 are not in contact with the inner surface of the through hole 113.

[0116] Then, the user presses the switch of the electrothermal conversion direct heating device 1 to start the electrical connection between the electrothermal conversion direct heating device 1 and the main control module of the external smoking device. The electrothermal conversion element 111 starts to heat up and directly heats the middle tobacco section 22. At the same time, the main control module of the smoking device detects the temperature change of the electrothermal conversion element 111 in real time.

[0117] After the middle tobacco section 22 is heated to the preset time, the main control module of the smoking device detects that the temperature of the electrothermal conversion element 111 has reached the preset temperature value, and prompts the user to smoke. At this time, the user sucks into the second end sponge section 23, which serves as the mouthpiece. At this time, because the protrusion 122 at the opening 121 fixes the second end sponge segment 23, the tobacco product 2 will not be carried out of the receiving cavity during inhalation. Furthermore, due to the closed structure at one end of the receiving cavity, the first end sponge segment 21 abuts against the closed end step 131 of the receiving cavity to form a ventilation chamber 6. During inhalation, as indicated by the arrow in Figure 6, air flows from the opening 121 along the groove formed by the protrusion 122 squeezing the tobacco product 2 into the ventilation chamber 6. The air in the ventilation chamber 6 passes through the first end sponge segment 21 and the middle tobacco segment 22 and is drawn out from the second end sponge segment 23 under the action of suction. The air is heated during the process of entering the ventilation chamber 6 from the opening 121. The air in the ventilation chamber 6 is always preheated, which can ensure that the internal temperature change of the middle tobacco segment 22 is small. At the same time, when the air enters from the opening 121, the heat on the surface of the second end sponge segment 23 near the opening 121 is carried into the ventilation chamber 6, effectively reducing the surface temperature of the second sponge segment 23. It helps solve the problem of burning the mouth, while also reducing the suction resistance for users.

[0118] The method for preparing the electrothermal conversion direct heating device for tobacco products according to the embodiments of this application is simple in preparation, has good consistency, simple structure, and convenient assembly. It can be customized independently according to different tobacco products. The hollow structure formed by the prepared electrothermal conversion direct heating device can directly heat the tobacco shreds. The hollow cavity can form an air insulation chamber with the heat insulation cotton, so that the heat loss of the electrothermal conversion element is small, the heating efficiency is high, the tobacco shreds are precisely heated, and the heating area is large and uniform. The heating effect can be quickly achieved without excessively high heating temperature, so that the surface of the tobacco product will not be scorched. One end of the tobacco product is inserted from the other end of the neck piece, passing through the heating device of the hollow structure and abutting against the step of the positioning seat, which can form an air exchange chamber. Combined with the opening of the neck piece of the hollow structure, an air circulation channel is formed, which reduces the resistance when smoking the tobacco product. The other end of the tobacco product located at the opening of the neck piece serves as a mouthpiece and will not burn the mouth. Furthermore, the tobacco product is locked by the neck piece and will not be pulled out of the heating device of the hollow structure when the user smokes the mouthpiece.

[0119] The electrothermal conversion direct heating device 1 prepared by the method of this application embodiment for preparing an electrothermal conversion direct heating device for tobacco products, forms a heating cavity by in-mold injection molding of an electrothermal conversion element 11 and an injection molded part 12, which surrounds the tobacco shreds 22 of the tobacco product 2, directly and precisely heating the tobacco product 2. Multiple hollow cavities 121 on the outer surface of the injection molded part 12 can form an air insulation chamber, which has less heat loss than traditional indirect heating, making the tobacco shreds 22 heat up quickly and with high heating efficiency. It can achieve the heating effect without excessively high temperatures, avoiding the surface of the tobacco product 2 from burning while the internal temperature of the tobacco shreds 22 has not reached the smoking temperature. Furthermore, one end of the tobacco product 2 abuts against the closed end of the heating cavity to form an air exchange chamber 4, which, together with the opening 122, forms an air circulation channel, making the resistance to smoking the tobacco product 2 low. The other end of the tobacco product 2 located at the opening 122 serves as a mouthpiece and will not burn the mouth. Moreover, the tobacco product 2 is locked in place by the opening 122 of the injection molded part 12, preventing the tobacco product 2 from being pulled out of the through hole when the user smokes through the mouthpiece.

[0120] The electrothermal conversion direct heating device 1 of this application, through experiments, shows that it can heat tobacco product 2 to the preset temperature in 20 seconds, and the tobacco shreds 22 can reach the state of generating aerosol. The preset temperature is below 260°C, and after 20 seconds, maintaining a temperature below 200°C can continuously generate aerosol. Current heating devices usually require heating to above 300°C for 25 seconds to reach the state of generating aerosol. In comparison, this application has a fast heating speed, low heat loss, high heating efficiency, large and uniform heating area, and flexible structure that can be adapted to different tobacco products, effectively solving the problem of burning the mouth.

[0121] The above description is merely a preferred embodiment of this application. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this application. Furthermore, under the teachings of this application, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this application. Therefore, this application is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this application.

Claims

1. An electrothermal conversion direct heating device for tobacco products, the electrothermal conversion direct heating device being configured to heat the tobacco products to generate aerosol, characterized in that, The electrothermal conversion direct heating device includes: An integrally molded heating device includes an electrothermal conversion element and an injection molded part, which are combined by in-mold injection molding. The injection molded part is formed and fixes the electrothermal conversion element during the in-mold injection molding process. The inner surface of the injection molded part and the inner surface of the electrothermal conversion element are on the same curved surface, and a through hole is formed for accommodating the tobacco product. Both ends of the electrothermal conversion element are exposed on the outer surface of the injection molded part for connecting external conductive pins. The heating device has one or more hollow cavities for forming an air insulation chamber. The neck component is a hollow structure, with one end of the neck component connected to one end of the injection molded part, and the other end of the neck component having an opening. A positioning seat, one end of which is an open structure and the other end is a closed structure; the open structure at one end of the positioning seat is connected to the other end of the injection molded part; the inner bottom of the closed structure of the positioning seat has at least one step for limiting the tobacco product. One end of the tobacco product is inserted through the opening of the neck piece, passes through the through hole into the positioning seat, and abuts against the step to form an air exchange chamber; the other end of the tobacco product extends out from the opening as a mouthpiece, the tobacco product is secured by the neck piece, and is directly heated by the electrothermal conversion element.

2. The electrothermal conversion direct heating device according to claim 1, characterized in that, Both ends of the heating device are equipped with heat insulation rings. The heat insulation rings are integrated with one end of the neck piece and one end of the positioning seat opening structure to form a receiving cavity for placing tobacco products. The tobacco products extend from the opening at the other end of the neck piece.

3. The electrothermal conversion direct heating device according to claim 1, characterized in that, The electrothermal conversion element includes one or more spiral coils, the inner surface of the spiral coil and the inner surface of the injection molded part are on the same curved surface; the injection molded part is combined with the spiral coil by in-mold injection molding, the spiral coil is fixed after in-mold injection molding, a distance is maintained between two adjacent spiral coils, and the outer surface of the spiral coil is exposed in the hollow cavity formed by the injection molded part.

4. The electrothermal conversion direct heating device according to claim 3, characterized in that, The spiral coil is circular or raceway-shaped, so that the through hole is cylindrical or raceway-shaped.

5. The electrothermal conversion direct heating device according to claim 4, characterized in that, The inner surface of the through hole has at least two grooves between it and the outer surface of the tobacco product. The opening of the neck piece, the grooves, and the ventilation chamber form an air circulation channel.

6. The electrothermal conversion direct heating device according to claim 5, characterized in that, The internal shape of the opening of the neck piece matches the shape of the through hole, and at least two protrusions are provided at the center of the opening. The tobacco product can be deformed by the protrusions and form the groove when passing through the through hole.

7. The electrothermal conversion direct heating device according to claim 5, characterized in that, When the through hole is shaped like a racetrack cylindrical hole, the length of the line connecting the two bends of the racetrack cylindrical hole is greater than or equal to the cross-sectional diameter of the tobacco product, and the length of the line connecting the two straight sections of the racetrack cylindrical hole is less than or equal to the cross-sectional diameter of the tobacco product.

8. The electrothermal conversion direct heating device according to claim 1, characterized in that, The electrothermal conversion direct heating device also includes thermal insulation cotton, which wraps the outer surface of the injection molded part, and the thermal insulation cotton and the hollow cavity form an air insulation chamber.

9. The electrothermal conversion direct heating device according to claim 8, characterized in that, Several hollow cavities are evenly distributed around the circumference of the injection molded part, and the thermal insulation cotton wraps the outer surface of the injection molded part. The hollow cavities and the thermal insulation cotton form an air insulation chamber.

10. A method for preparing an electrothermal conversion direct heating device for tobacco products, characterized in that, include: Alloy plates are selected and manufactured into electrothermal conversion elements with their inner surfaces on the same curved surface; The first mold for the heating element, the second mold for the neck part, and the third mold for the positioning seat are manufactured. The electrothermal conversion element is fixed in the cavity of the first mold. Plastic is filled into the cavity of the first mold by an injection molding machine so that the electrothermal conversion element and the plastic are combined in the cavity of the first mold to form a hollow heating device. The injection molded part is formed during the injection molding process and forms multiple hollow cavities to expose part of the outer surface of the electrothermal conversion element. The obtained heating device is taken out from the cavity of the first mold. Conductive leads are welded to both ends of the electrothermal conversion element exposed on the outer surface of the injection molded part; The neck part is formed into a hollow structure by filling the cavity of the second mold with injection molding machine. The obtained neck part is removed from the cavity of the second mold, or the sheet metal is processed by machining to obtain a hollow neck part. Plastic is filled into the cavity of the third mold by an injection molding machine. The positioning seat is formed into a structure with one end open and the other end closed during the injection molding process, and at least one step is formed at the bottom of the closed structure. The obtained positioning seat is then removed from the cavity of the third mold. The neck piece is fixedly connected to one end of the injection molded part, and one end of the opening structure of the positioning seat is fixedly connected to the other end of the injection molded part to obtain an electrothermal conversion direct heating device.

11. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 10, characterized in that, The selected alloy plate is used to fabricate an electrothermal conversion element with its inner surface on the same curved surface, including: Select strip-shaped plates made of alloy material; The strip material is wound according to a preset shape, preset number of turns and spacing to form a spiral coil with one or more turns and spacing, and the inner surfaces of the spiral coil are on the same curved surface.

12. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 11, characterized in that, The selected alloy plate is used to fabricate an electrothermal conversion element with its inner surface on the same curved surface, including: Select a tubular plate of a preset size; The tubular plate is laser-cut according to a preset number of turns to form a spiral coil with one or more turns at a preset spacing, and the inner surfaces of the spiral coils are on the same curved surface.

13. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 12, characterized in that, The spiral coil is circular or raceway-shaped, and the inner surface of the spiral coil is cylindrical or raceway-shaped.

14. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 10, characterized in that, The alloy material includes at least two of nickel, chromium, iron, copper, molybdenum, manganese, silver, silicon, antimony, niobium, sulfur, and phosphorus, or any one of nickel-chromium alloy, iron-chromium-aluminum alloy, nickel-copper alloy, and stainless steel alloy.

15. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 10, characterized in that, After welding conductive pins to both ends of the electrothermal conversion element exposed on the outer surface of the injection molded part, the manufacturing method further includes: The temperature sensor is attached to the outer surface of the electrothermal conversion element, and the pins of the temperature sensor extend from the outer surface of the injection molded part.

16. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 15, characterized in that, After welding conductive pins to both ends of the electrothermal conversion element exposed on the outer surface of the injection molded part, the manufacturing method further includes: Insulating cotton is wrapped around the outer surface of the injection molded part to cover the hollow cavity and the temperature sensor.

17. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 10, characterized in that, After removing the obtained heating device from the cavity of the first mold, the preparation method further includes: Heat insulation rings are placed at both ends of the injection molded part.

18. The method for preparing the electrothermal conversion direct heating device for tobacco products according to claim 17, characterized in that, The step of fixing one end of the neck piece to one end of the injection molded part and fixing one end of the positioning seat opening structure to the other end of the injection molded part includes: After placing the heat insulation ring at one end of the injection molded part, a portion of one end of the injection molded part is inserted into the hollow structure of the neck member, and an interference fit is used to fix one end of the injection molded part to the neck member; after placing the heat insulation ring at the other end of the injection molded part, a portion of the other end of the injection molded part is inserted into one end of the positioning seat opening structure, and an interference fit is used to fix the other end of the injection molded part to one end of the positioning seat opening structure.

19. A direct heating device for electrothermal conversion in tobacco products, characterized in that, It is prepared by the method of preparing an electrothermal conversion direct heating device for tobacco products as described in any one of claims 10-18.

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