Aerosol generating system and aerosol generating device

Abstract

The present invention relates to an aerosol generating system and an aerosol generating device. The aerosol generating system comprises an aerosol generating substrate and the aerosol generating device; the aerosol generating device comprises a fixing unit, and a cavity for accommodating at least part of the aerosol generating substrate is defined inside the fixing unit; the fixing unit is provided with an opening in communication with the cavity; the aerosol generating substrate comprises a substrate section and a support section which are sequentially accommodated in the cavity from the opening; the support section is arranged at one end of the substrate section; when the substrate section is accommodated in the cavity, an airflow channel is formed between the fixing unit and the aerosol generating substrate, and the airflow channel is in communication with the opening; the airflow channel comprises a first channel section in communication with the opening and a second channel section; and the second channel section is in communication with the first channel section, and the width of the first channel section is less than the width of the second channel section. The aerosol generating system reasonably distributes the draw resistance to achieve a constant resistance during puffing.

Description

Aerosol generation system and aerosol generation device Technical Field

[0001] This invention relates to the field of atomization, and more particularly to aerosol generation systems and aerosol generation devices. Background Technology

[0002] Aerosol generating devices in related technologies typically employ heated non-combustible technology, with heating temperatures generally between 250 and 350°C. Compared to conventional combustion aerosol generating devices, heated non-combustible aerosol generating devices can significantly reduce the release of harmful substances from the matrix while preserving the traditional aerosol flavor.

[0003] In relevant aerosol generating devices, the aerosol generating matrix is ​​heated and then transported to the user through a specific U-shaped airway. Taking a conventional U-shaped airway as an example, air flows from top to bottom and enters the medium through the bottom, carrying the aerosol into the user's mouth. The suction resistance during the suction process depends on the magnitude of the frictional resistance generated by the air and aerosol flow. Often, as the heating process proceeds, the diameter of the aerosol generating matrix changes, which affects the frictional resistance of the air section, resulting in a noticeable change in suction resistance for the user. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an improved aerosol generation system and aerosol generation device.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to construct an aerosol generation system, including an aerosol generation matrix and an aerosol generation device; the aerosol generation device includes a fixing unit, the inner side of which defines a cavity for accommodating at least part of the aerosol generation matrix; and the fixing unit is provided with an opening communicating with the cavity.

[0006] The aerosol generating matrix includes a matrix segment and a support segment sequentially housed in the cavity from the opening; the support segment is disposed at one end of the matrix segment;

[0007] When the matrix segment is housed in the cavity, an airflow channel is formed between the fixing unit and the aerosol generating matrix, and the airflow channel is connected to the opening.

[0008] The airflow channel includes a first channel segment formed between the fixing unit and the support segment and communicating with the opening, and a second channel segment formed between the fixing unit and the matrix segment; the second channel segment communicates with the first channel segment, and the width of the first channel segment is smaller than the width of the second channel segment.

[0009] In some embodiments, the cavity includes a first space and a second space arranged sequentially along the axial direction of the fixing unit; the first space is located at the end of the second space away from the opening;

[0010] The first space has a first dimension in a direction perpendicular to the axial direction of the fixing unit;

[0011] The second space has a second dimension in a direction perpendicular to the axial direction of the fixing unit;

[0012] The first dimension is larger than the second dimension.

[0013] In some embodiments, the inner wall of the fixing unit is provided with an airflow groove, which extends from the opening toward the second space;

[0014] The airflow channel defines at least a portion of the airflow passage.

[0015] In some embodiments, the fixing unit includes a first pipe segment and a second pipe segment; the second pipe segment is disposed at one end of the first pipe segment and is coaxially disposed with the first pipe segment;

[0016] The first space is formed in the first pipe segment; the opening is located at the end of the first pipe segment away from the second pipe segment;

[0017] The second space is formed in the second pipe segment.

[0018] In some embodiments, the airflow channel is disposed on the inner wall of the first pipe section.

[0019] In some embodiments, there are multiple airflow channels, which are spaced apart circumferentially along the fixing unit.

[0020] In some embodiments, a sensing air passage is provided on the side wall of the fixing unit, and the sensing air passage is connected to the airflow channel.

[0021] In some embodiments, the fixing unit includes a support wall disposed opposite to the opening;

[0022] The airflow channel extends at least partially from the opening to the support wall.

[0023] In some embodiments, the aerosol generation system includes a heating structure; the heating structure includes at least one of a microwave radiation structure, a resistance heating structure, and an electromagnetic heating structure.

[0024] The support wall is provided with perforations for the heating structure to pass through into the cavity.

[0025] The present invention also provides an aerosol generating device, including a fixing unit, wherein the inner side of the fixing unit defines a cavity for accommodating at least a portion of the aerosol generating matrix; and the fixing unit is provided with an opening communicating with the cavity; and an airflow channel communicating with the opening is formed in the fixing unit.

[0026] The airflow channel includes a first channel segment and a second channel segment connected to the opening; the second channel segment is connected to the first channel segment, and the width of the first channel segment is smaller than the width of the second channel segment.

[0027] The aerosol generation system and aerosol generation device of the present invention have the following beneficial effects: The aerosol generation system forms an airflow channel between the fixed unit and the aerosol generation matrix, and the width of the first channel segment formed between the fixed unit and the support segment of the aerosol generation matrix is ​​smaller than the width of the second channel segment formed between the fixed unit and the matrix segment. This allows for a reasonable distribution of suction resistance to achieve constant resistance during the suction process, reducing the variation in suction resistance during the suction process and thus improving the user's suction experience. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0029] Figure 1 is a schematic diagram of the structure of the aerosol generating device and the aerosol generating matrix of the aerosol generating system of the present invention.

[0030] Figure 2 is a schematic diagram of the structure of the fixed unit of the aerosol generating device shown in Figure 1;

[0031] Figure 3 is a cross-sectional view of the fixed unit shown in Figure 2;

[0032] Figure 4 is a simulation diagram of the first inlet resistance distribution of the aerosol generation system of the present invention.

[0033] Figure 5 is a simulation diagram of the final resistance distribution of the aerosol generation system of the present invention.

[0034] Figure 6 is a simulation diagram of the first-stage resistance distribution of a conventional aerosol generation system.

[0035] Figure 7 is a simulation diagram of the final resistance distribution of a conventional aerosol generation system. Detailed Implementation

[0036] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the following description, it should be understood that the terms "upper," "inner," "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific orientation. They are only for the convenience of describing the technical solution and do not indicate that the device or element referred to must have a specific orientation; therefore, they should not be construed as limitations on the present invention.

[0037] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "connection," "fixed," and "set" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two elements or the interaction between two elements. When an element is referred to as being "on" or "below" another element, that element can be located "directly" or "indirectly" on the other element, or there may be one or more intermediary elements. The terms "first," "second," "third," etc., are only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," "third," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0038] Figure 1 illustrates some preferred embodiments of the aerosol generation system of the present invention. The aerosol generation system includes an aerosol generation matrix and an aerosol generation device, which heats the aerosol generation matrix 100 using a heating-without-combustion method. In some embodiments, the aerosol generation device can use microwave heating to heat the aerosol generation matrix 100, which has the advantages of high heating efficiency and rapid aerosol generation. The principle of microwave heating of the aerosol generation device is generally based on a quarter-wavelength coaxial resonant cavity with an open-circuit end of the inner conductor unit. After the aerosol generation matrix 100 is added, the resonant cavity will resonate at the resonant frequency, thereby achieving rapid heating of the aerosol generation matrix 100.

[0039] Understandably, in some other embodiments, the aerosol generating device is not limited to microwave heating; it may use resistance heating or electromagnetic heating to heat the aerosol generating matrix 100.

[0040] In some embodiments, the aerosol generating matrix 100 is generally cylindrical, specifically, it may be substantially cylindrical. The aerosol generating matrix 100 may include a matrix segment 101, a support segment 102, a cooling segment (not shown), and a filtration segment (not shown). In this embodiment, the matrix segment 101 may be a solid material in the form of strips, sheets, granules, or integral molding made from the leaves and / or stems of a plant (e.g., tobacco), and aroma components may be further added to this solid material. The support segment 102 is disposed at one end of the matrix segment 101 and serves to support the matrix segment 101. The support segment 102 may be a hollow tube. In some embodiments, a plug segment (not shown) may be provided at the end of the matrix segment 101 away from the support segment 102. The cooling segment (not shown) may be disposed at the end of the support segment 102 away from the matrix segment 101, and it may be a hollow tube. In some embodiments, a filter section (not shown) is disposed at the end of the cooling section (not shown) away from the support section 102. In some embodiments, the filter section (not shown) may be filter cotton. In some embodiments, the aerosol generating matrix 100 may further include an outer packaging structure covering the periphery of the plug section (not shown), matrix section 101, support section 102, cooling section (not shown), and filter section (not shown). In some embodiments, the outer packaging structure may be a paper material. In other embodiments, the aerosol generating matrix 100 is not limited to the sections listed above, and may also include other functional sections.

[0041] In some embodiments, the aerosol generating device may include a housing (not shown), a microwave heating assembly, and a microwave generating unit (not shown). The microwave heating assembly is housed within the housing (not shown) and is used to generate a microwave forming energy field within it after microwaves are introduced, thereby heating the aerosol generating matrix 100. The microwave generating unit (not shown) may be connected to the microwave heating assembly for feeding microwaves.

[0042] In some embodiments, the microwave heating assembly may include a fixing unit 10, which can be used to fix the aerosol generating matrix 100, ensuring that the relative position of the aerosol generating matrix 100 and the heating assembly remains unchanged during heating, thereby ensuring the consistency of heating and the stability of suction. At the same time, the fixing unit 10 can effectively prevent condensate from leaking onto the heating assembly, causing the heating assembly to fail, and also makes it easier for users to clean the oil stains caused by repeated suction.

[0043] In some embodiments, the fixing unit 10 may be made of a lossless or low-loss dielectric material. For example, the fixing unit 10 may be made of Teflon, PEEK, quartz, alumina ceramic, various composite wave-transparent materials, etc.

[0044] As shown in Figures 1 to 3, in some embodiments, the fixing unit 10 can be a cylindrical structure or a tubular structure. The fixing unit 10 may include a first pipe segment 11 and a second pipe segment 12. The second pipe segment 12 is disposed at one end of the first pipe segment 11 and is coaxially arranged with the first pipe segment 11. In some embodiments, the cross-sections of the first pipe segment 11 and the second pipe segment 12 may be circular, the outer diameter of the first pipe segment 11 may be smaller than the outer diameter of the second pipe segment 12, and the first pipe segment 11 and the second pipe segment 12 may be stepped together. In some embodiments, the first pipe segment 11 and the second pipe segment 12 may be an integrally formed structure.

[0045] In other embodiments, the cross-sections of the first pipe segment 11 and the second pipe segment 12 are not limited to circular shapes; for example, they can be square, elliptical, or other shapes. The outer diameters of the first pipe segment 11 and the second pipe segment 12 can also be equal. In some embodiments, the first pipe segment 11 and the second pipe segment 12 can also be detachably connected, such as by plugging in.

[0046] In some embodiments, the fixing unit 10 is hollow inside to define a cavity 13, which can accommodate at least a portion of the aerosol generating matrix 100. Specifically, the cavity 13 can extend from the first pipe segment 11 to the second pipe segment 12. The fixing unit 10 is provided with an opening 14 that can communicate with the cavity 13, and the opening 14 is located at the end of the first pipe segment 11 away from the second pipe segment 12.

[0047] In some embodiments, the cavity 13 is a cylindrical cavity. In some embodiments, the cavity 13 may include a first space 13a and a second space 13b arranged sequentially along the axial direction; wherein the first space 13a is disposed at the end of the second space 13b away from the opening 14. In some embodiments, the first space 13a is formed in a first pipe segment 11, and the second space 13b is formed in a second pipe segment 12.

[0048] In some embodiments, the first space 13a has a first dimension in a direction perpendicular to the axial direction of the fixing unit 10, and the second space 13b has a second dimension in a direction perpendicular to the axial direction of the fixing unit 10, wherein the first dimension is larger than the second dimension.

[0049] For example, the cross-sections of the first space 13a and the second space 13b may be approximately circular. The first space 13a has a first radial dimension in the radial direction (also perpendicular to the axial direction of the fixing unit 10); the second space 13b has a second radial dimension in the radial direction (also perpendicular to the axial direction of the fixing unit 10), and the first radial dimension may be larger than the second radial dimension. Generally, the radial dimension of the first space 13a can be made larger than the radial dimension of the second space 13b by increasing the thickness of the second pipe segment 12, making the thickness of the second pipe segment 12 greater than the thickness of the first pipe segment 11.

[0050] In some other embodiments, the cross-sections of the first space 13a and the second space 13b may be generally rectangular. The first space 13a has a first length and a first width in the transverse direction (the direction perpendicular to the axis of the fixing unit 10); the second space 13b has a second length and a second width in the transverse direction (the direction perpendicular to the axis of the fixing unit 10); wherein the first length is greater than the second length; and the first width may be greater than the second width.

[0051] In some other embodiments, the cross-sections of the first space 13a and the second space 13b are not limited to the shapes listed above; they may also be elliptical, square, or other shapes.

[0052] In some embodiments, the opening 14 may be generally funnel-shaped and may be narrowed toward the second tube segment 13b so that the aerosol generating matrix 100 may be at least partially inserted into the cavity 13.

[0053] In some embodiments, the fixing unit 10 further includes a support wall 15, which may be disposed opposite to the opening 14 and may be disposed at the end of the first pipe segment 11 away from the opening 14. The support wall 15 may be integrally formed with the first pipe segment 11. In some embodiments, the support wall 15 has a through hole 151, which is disposed at the central axis of the support wall 15 and extends through the support wall 15 along the thickness direction for a heating structure (not shown) to pass through.

[0054] In some embodiments, the support wall 15 has a protrusion 152 protruding from the side facing the cavity 13. The protrusion 152 may be located at the central axis of the support wall 15, and the perforation 151 may be formed in the protrusion 152. The protrusion 152 can serve to support the aerosol generating matrix 100. In some embodiments, the protrusion 152 is not limited to being located at the central axis of the support wall 15; it may be located on the outer periphery of the perforation 151. There may be at least two protrusions 152, which may be spaced apart circumferentially along the support wall 15, and an air inlet groove may be formed between two adjacent protrusions 152. In some embodiments, the protrusion 152 may also be omitted.

[0055] In some embodiments, the inner wall of the fixing unit 10 is provided with an airflow groove 16, which extends from the opening 14 into the second space 13b. Specifically, the airflow groove 16 may be disposed on the inner wall of the second pipe segment 12. In some embodiments, there may be multiple airflow grooves 16, which may be spaced apart circumferentially along the second pipe segment 12. In other embodiments, the airflow groove 16 may also extend from the opening 14 to the support wall 15.

[0056] In some embodiments, a sensing air passage 17 is provided on the side wall of the fixing unit 10. The sensing air passage 17 can communicate with the airflow channel 16 and is connected to the airflow sensor to facilitate airflow to trigger the airflow sensor. In some embodiments, the sensing air passage 17 can be formed by opening an airflow hole in the side wall of the second pipe section 12. In some embodiments, the sensing air passage 17 can also be omitted.

[0057] In some embodiments, the aerosol generating matrix 100 can be inserted into the cavity 13 through the opening 14. When the aerosol generating matrix 100 is assembled with the fixing unit 10, the matrix segment 101 and the support segment 102 can be sequentially accommodated in the cavity 13 through the opening 14. The matrix segment 101 can be entirely located in the first space 13a, and the support segment 102 can be partially located outside the opening 14. In some embodiments, when the matrix segment 101 is accommodated in the cavity 13, an airflow channel 18 is formed between the fixing unit 10 and the aerosol generating matrix 100. The airflow channel 18 can communicate with the opening 14 and can extend to the support wall 15. The sensing air passage 17 can communicate with the airflow channel 18. When suction is performed, airflow enters from the airflow channel 18, and part of the airflow can enter the airflow sensor through the sensing air passage 17.

[0058] In some embodiments, the airflow channel 18 may include a first channel segment 181 and a second channel segment 182. The first channel segment 181 is formed between the fixing unit 10 and the support segment 102. The airflow channel 16 defines the first channel segment 181 of the airflow channel 18. The second channel segment 182 is formed between the fixing unit 10 and the matrix segment 101. Specifically, the first channel segment 181 may be formed between the second pipe segment 12 and the support segment 102, and the second channel segment 182 may be formed between the first pipe segment 11 and the matrix segment 101. The first channel segment 181 may communicate with the second channel segment 182. The second channel segment 182 may extend to the support wall 15. External airflow may enter the first channel segment 181 from the opening 14 and then enter the second channel segment 182, then flow into the sealing segment (not shown) of the aerosol generating matrix 100, and finally enter the matrix segment 101, carrying the heated and released aerosol through the support segment 102, the cooling segment (not shown), and the filtering segment (not shown) into the mouth of the person receiving the aspiration.

[0059] In some embodiments, the width W1 of the first channel segment 181 is smaller than the width W2 of the second channel segment 182, that is, the gap between the first tube segment 11 and the matrix segment 101 is larger than the gap between the second tube segment 12 and the support segment 102. This allows for a reasonable distribution of suction resistance to achieve constant resistance during the suction process, reducing the variation in suction resistance during the suction process and thus improving the user's suction experience.

[0060] It should be noted that the suction resistance of the aerosol generation system mainly consists of three factors: the frictional resistance along the airflow channel 18, the resistance of the air passage in the matrix section 101, and the internal flow resistance of the matrix section 101. During suction, the diameter of the matrix section 101 decreases, while the width of the second channel section 182 of the conventional airflow channel increases significantly, resulting in a decrease in suction resistance (the change in suction resistance can be ΔF1). This leads to a noticeable inconsistency in the user's experience before and after suction. This application addresses this by widening the second channel section 182, making it larger than the first channel section 181. This reduces the width change of the second channel section 182 during suction, thereby reducing the change in suction resistance (i.e., the change in suction resistance of the aerosol generation system in this application can be ΔF2, where ΔF2 is less than ΔF1). This ensures consistency in the experience before and after suction, or only a slight difference in resistance, improving the user's suction experience.

[0061] In some embodiments, the microwave heating assembly further includes a heating structure (not shown). Specifically, the heating structure (not shown) can be a microwave radiating structure. The microwave heating assembly may include an inner conductor unit (not shown) that includes the microwave radiating structure. The microwave radiating structure (not shown) can be columnar and can penetrate into the cavity 13 through the perforation 151. The microwave radiating structure (not shown) can be inserted into the aerosol generating matrix 100, and the matrix segment 101 is heated by radiating microwaves to generate aerosols. The inner conductor unit (not shown) may also include an impedance matching structure connected to the microwave radiating structure (not shown). In some embodiments, the inner conductor unit (not shown) can be connected to a microwave feed unit.

[0062] In some embodiments, the microwave heating assembly further includes an outer conductor unit (not shown), which may be disposed on the outer periphery of the fixed unit 10 and cooperate with the microwave radiation structure (not shown). Specifically, it may be connected to the inner conductor unit (not shown), thereby enabling the microwave radiation structure (not shown) to radiate microwaves.

[0063] In some other embodiments, the fixing unit 10 may also be an outer conductor unit (not shown), that is, there is no need to set an additional outer conductor unit (not shown).

[0064] In some other embodiments, the heating structure is not limited to a microwave radiation structure; it can be a resistance heating structure or an electromagnetic heating structure.

[0065] The simulation comparison between the aerosol generation system of this application and a conventional aerosol generation system is shown in the table below:

[0066]

[0067] As shown in the table above and Figures 4 to 7, the difference in suction resistance between the first and last inhalation of the aerosol generation system using this application is less than 5%, which means that the change in suction resistance before and after suction in the aerosol generation system of this application is small, resulting in a high user experience.

[0068] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. An aerosol generation system, comprising an aerosol generation matrix (100) and an aerosol generation device; characterized in that, The aerosol generating device includes a fixing unit (10), the inner side of which defines a cavity (13) for accommodating at least a portion of the aerosol generating matrix (100); and the fixing unit (10) is provided with an opening (14) communicating with the cavity (13). The aerosol generating matrix (100) includes a matrix segment (101) and a support segment (102) sequentially housed in the cavity (13) from the opening (14); the support segment (102) is disposed at one end of the matrix segment (101); When the matrix segment (101) is housed in the cavity (13), an airflow channel (18) is formed between the fixing unit (10) and the aerosol generating matrix (100), and the airflow channel (18) is connected to the opening (14); The airflow channel (18) includes a first channel segment (181) formed between the fixing unit (10) and the support segment (102) and communicating with the opening (14), and a second channel segment (182) formed between the fixing unit (10) and the matrix segment (101); the second channel segment (182) communicates with the first channel segment (181), and the width of the first channel segment (181) is smaller than the width of the second channel segment (182).

2. The aerosol generation system according to claim 1, characterized in that, The cavity (13) includes a first space (13a) and a second space (13b) arranged sequentially along the axial direction of the fixing unit (10); the first space (13a) is located at the end of the second space (13b) away from the opening (14); The first space (13a) has a first dimension in a direction perpendicular to the axial direction of the fixing unit (10); The second space (13b) has a second dimension in a direction perpendicular to the axial direction of the fixing unit (10); The first dimension is larger than the second dimension.

3. The aerosol generation system according to claim 2, characterized in that, The inner wall of the fixing unit (10) is provided with an air passage (16), which extends from the opening (14) to the second space (13b); The airflow channel (16) defines at least a portion of the airflow passage (18).

4. The aerosol generation system according to claim 3, characterized in that, The fixing unit (10) includes a first pipe section (11) and a second pipe section (12); the second pipe section (12) is disposed at one end of the first pipe section (11) and is coaxially disposed with the first pipe section (11); The first space (13a) is formed in the first pipe segment (11); the opening (14) is located at the end of the first pipe segment (11) away from the second pipe segment (12); The second space (13b) is formed in the second pipe segment (12).

5. The aerosol generation system according to claim 4, characterized in that, The airflow channel (16) is disposed on the inner wall of the first pipe section (11).

6. The aerosol generation system according to claim 3, characterized in that, There are multiple airflow channels (16), and the multiple airflow channels (16) are arranged at circumferential intervals along the fixed unit (10).

7. The aerosol generation system according to claim 1, characterized in that, The side wall of the fixed unit (10) is provided with a sensing air channel (17), which is connected to the airflow channel (18).

8. The aerosol generation system according to claim 1, characterized in that, The fixing unit (10) includes a support wall (15) disposed opposite to the opening (14); The airflow channel (18) extends at least partially from the opening (14) to the support wall (15).

9. The aerosol generation system according to claim 8, characterized in that, The aerosol generation system includes a heating structure; the heating structure includes at least one of a microwave radiation structure, a resistance heating structure, and an electromagnetic heating structure. The support wall (15) is provided with a perforation (151) for the heating structure to pass through into the cavity (13).

10. An aerosol generating device, characterized in that, The device includes a fixing unit (10), the inner side of which defines a cavity (13) for accommodating at least a portion of the aerosol generating matrix (100); and the fixing unit (10) is provided with an opening (14) communicating with the cavity (13); and an airflow channel (18) communicating with the opening (14) is formed in the fixing unit (10). The airflow channel (18) includes a first channel segment (181) and a second channel segment (182) connected to the opening (14); the second channel segment (182) is connected to the first channel segment (181), and the width of the first channel segment (181) is smaller than the width of the second channel segment (182).

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