Smoke ducts and range hoods

Abstract

The application provides a smoke guide pipe and an extractor hood. The smoke guide pipe comprises a first pipe and a second pipe, the first pipe and the second pipe are connected oppositely to form an outer pipe wall surface and an inner smoke guide channel, and the outer pipe wall surface is provided with a first driving transmission mechanism capable of swinging the first pipe relative to the second pipe. The first driving transmission mechanism is arranged on the outer pipe wall surface, which can not only swing left and right according to the position and size of the oil smoke to capture the oil smoke, but also can reduce the influence of oil dirt on the first driving transmission mechanism, increase the service life, and facilitate the replacement operation of the first driving transmission mechanism.

Description

Technical Field

[0001] The present invention relates to the technical field of range hoods, and in particular to a smoke guide pipe and a range hood. Background Art

[0002] A range hood is a kitchen appliance that purifies the kitchen environment. Installed above the stove, it quickly extracts waste from combustion and harmful cooking fumes, exhausting them outdoors. It also condenses and collects the fumes, reducing pollution and purifying the air. However, most existing range hoods suffer from issues such as escaping smoke and failing to capture them based on their location and size.

[0003] In response to the above problems, range hoods have emerged that can adjust the position and direction of the smoke outlet according to the position and size of the oil smoke. For example, the structure disclosed in the Chinese invention patent application with publication number CN112212383A published on January 12, 2021, improves the escape of oil smoke by setting a rotatable air duct. However, since the drive device and the universal mount are placed inside the air duct, the air duct is the main position for the range hood to absorb oil. After long-term use, oil stains can easily penetrate into the motor assembly of the universal mount and the drive device, affecting the service life, and it is also very inconvenient to replace the universal mount and motor assembly later. Summary of the Invention

[0004] In order to at least partially solve the problems existing in the prior art, a smoke guide tube is provided, which includes a first tube and a second tube, the first tube and the second tube being connected to each other to form an outer tube wall and an internal smoke guide channel, and a first driving transmission mechanism is provided on the outer tube wall to enable the first tube to swing relative to the second tube.

[0005] The above-mentioned smoke guide pipe, since it is connected to the first pipe and the second pipe and a first drive transmission mechanism is provided on the outer pipe wall, can not only swing left and right according to the position and size of the oil smoke to capture the oil smoke, but also reduce the impact of oil pollution on the first drive transmission mechanism, increase its service life, and facilitate the replacement operation of the first drive transmission mechanism.

[0006] Exemplarily, the first tube has a first end and a second end, the first end having a smoking port, the second tube having a connecting end opposite the second end, the outer tube wall including a first outer tube wall located on the first tube and a second outer tube wall located on the second tube, the first drive transmission mechanism including a first drive device, a first transmission member, and a first follower, the first drive device being disposed on the first outer tube wall and having a first output shaft, the first follower being disposed on the connecting end, the first output shaft being connected to the first follower via the first transmission member so as to be able to drive the second tube; or the first drive device being disposed on the second outer tube wall and having a first output shaft, the first follower being disposed on the second end, the first output shaft being connected to the first follower via the first transmission member so as to be able to drive the first tube. In this manner, the first drive transmission mechanism is simple and easy to assemble, thereby making production convenient and quick, and improving production efficiency.

[0007] Exemplarily, the first tube includes a first inner tube and a first outer tube, the first outer tube is sleeved outside the first inner tube and fixedly connected to the first inner tube, the first outer tube wall is the outer side surface of the first outer tube, and the first outer tube has a first connecting section at the second end; the second tube includes a second inner tube and a second outer tube, the second outer tube is sleeved outside the second inner tube and fixedly connected to the second inner tube, the second outer tube wall is the outer side surface of the second outer tube, and the second outer tube has a second connecting section; the second connecting section is connected to the first connecting section via a bearing. In this way, the second connecting section and the first connecting section form a sealed connection area between the first tube and the second tube, which not only enables the first tube to swing smoothly relative to the second tube, thereby facilitating accurate capture of oil smoke according to the position and size of the oil smoke, but also prevents oil smoke from escaping from the internal smoke guide channel and affecting the service life of the first drive transmission mechanism.

[0008] For example, the smoke guide tube further includes a third tube having a third outer tube wall surface, a second drive device disposed on the third outer tube wall surface, the second drive device having a second output shaft, the second tube having a distal end away from the first tube, the distal end having a second follower, the second output shaft being connected to the second follower via a second transmission member to drive the second tube. In this manner, the first tube can simultaneously swing relative to the second tube, thereby more accurately capturing oil smoke based on its location and size.

[0009] For example, the third tube includes a third inner tube and a third outer tube. The third outer tube is sleeved outside the third inner tube and fixedly connected thereto. The third outer tube has a third connecting section. The second outer tube has a fourth connecting section spaced apart from the second connecting section. The third and fourth connecting sections are connected via a bearing. Thus, the third and fourth connecting sections form a sealed connection between the third tube and the second tube. This not only allows the third tube to swing smoothly relative to the second tube, thereby facilitating accurate capture of oil smoke based on its location and size, but also prevents oil smoke from escaping from the internal smoke guide channel and affecting the service life of the second drive device.

[0010] For example, a mating surface is formed between the first and second connecting segments, and between the third and fourth connecting segments. Each mating surface is inclined at an angle α relative to the central axis of the second outer tube and is elliptical with a major axis D1 and a minor axis D2, where D2 = D1 × cosα. This not only satisfies the swing requirements between the first and second tubes, and between the second and third tubes, but also ensures a tight connection between the first and second tubes, and between the second and third tubes, preventing smoke from escaping.

[0011] For example, D2 is 100 mm to 300 mm, and α is 15° to 35°. In this way, the smoke guide requirements of the range hood can be met, so that the range hood can be well used.

[0012] For example, the first drive device is a motor, the first transmission member is a first gear fixedly mounted on the first output shaft, the second outer tube has a first outer edge surface, the shape of the first outer edge surface being similar to the shape of the connecting mating surface, and the first driven member is a second gear fixedly mounted on the first outer edge surface and meshing with the first gear. In this manner, the gear transmission between the first and second tubes is simple in structure and convenient for assembly.

[0013] For example, the second driving device is a motor, the second transmission member is a third gear fixedly mounted on the second output shaft, the second outer tube has a second outer edge surface, the shape of which is similar to the shape of the connecting mating surface, and the second driven member is a fourth gear fixedly mounted on the second outer edge surface and meshing with the third gear. In this manner, the second and third tubes utilize a gear transmission method, which not only simplifies the structure but also facilitates assembly.

[0014] For example, the first inner tube has a first chute at the second end, and the second inner tube has a first connecting portion extending into the first chute; or the second inner tube has a first chute, and the first inner tube has a first connecting portion extending into the first chute at the second end. This prevents unnecessary interference between the first and second tubes during relative rotation.

[0015] For example, the third inner tube has an inner tube connection end connected to the second inner tube, the inner tube connection end having a second slot, and the second inner tube having a second connection portion extending into the second slot; or the second inner tube has an inner tube connection end connected to the third inner tube, the inner tube connection end having a second slot, and the third inner tube having a second connection portion extending into the second slot. In this way, unnecessary interference between the second and third tubes during relative rotation is avoided.

[0016] According to another aspect of the present invention, a range hood is provided, comprising a range hood housing and a smoke guide pipe disposed below the range hood housing, wherein the smoke guide pipe is the aforementioned smoke guide pipe. Since the aforementioned smoke guide pipe has the aforementioned beneficial effects, a range hood including the aforementioned smoke guide pipe will also necessarily have the aforementioned beneficial effects.

[0017] The advantages and features of the present invention are described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following drawings of the present invention are hereby incorporated into the present invention for understanding the present invention. The drawings show embodiments of the present invention and their descriptions, and are used to explain the principles of the present invention. In the drawings,

[0019] Figure 1 is a structural diagram of a range hood according to an exemplary embodiment of the present invention (seen from one direction);

[0020] Figure 2 is a structural diagram of a range hood according to an exemplary embodiment of the present invention (seen from another direction);

[0021] Figure 3 is an internal structural diagram of a range hood according to an exemplary embodiment of the present invention;

[0022] Figure 4 for Figure 3 A magnified view of part A in FIG;

[0023] Figure 5 for Figure 3 A magnified view of part B in FIG;

[0024] Figure 6 for Figure 2 Schematic diagram of the connection mating surface in;

[0025] Figure 7 for Figure 3 A partial cross-sectional view of the second tube in FIG;

[0026] Figure 8 for Figure 3 Schematic diagram of the connection between the first tube and the second tube;

[0027] Figure 9 for Figure 8 Enlarged view of part C in .

[0028] The above drawings include the following reference numerals:

[0029] 101—Outer tube wall

[0030] 1011—first outer tube wall

[0031] 1012—Second outer tube wall

[0032] 102—Internal smoke channel

[0033] 110—First tube

[0034] 1101—First End

[0035] 1102—Second end

[0036] 1103—Smoking area

[0037] 111—First inner tube

[0038] 1111—Chute

[0039] 112—First outer tube

[0040] 1121—First connecting section

[0041] 113—First connecting piece

[0042] 120—Second tube

[0043] 1201—Connection end

[0044] 1202—Far from the end

[0045] 121—Second inner tube

[0046] 1211—First connection

[0047] 1212—Second connection

[0048] 122—Second outer tube

[0049] 1221—Second connecting section

[0050] 1222—Fourth connecting section

[0051] 1223—First outer edge surface

[0052] 1224—Second outer edge surface

[0053] 123—Second connecting piece

[0054] 130—First drive transmission mechanism

[0055] 131—First drive motor

[0056] 1311—First output shaft

[0057] 132—First transmission member

[0058] 133—First follower

[0059] 140—Third tube

[0060] 1401—Third outer tube wall

[0061] 141—Third inner tube

[0062] 142—Third outer tube

[0063] 1421—Third connecting section

[0064] 143—Third connecting piece

[0065] 151—Second drive device

[0066] 1511—Second output shaft

[0067] 152—Second transmission member

[0068] 153—Second follower

[0069] 160—Connection mating surface

[0070] 170—Smoke hood

[0071] 171—first cover

[0072] 172—Second cover

[0073] 200—Smoke machine box DETAILED DESCRIPTION

[0074] In the following description, a large amount of detail is provided to facilitate a thorough understanding of the present invention. However, it will be appreciated by those skilled in the art that the following description merely illustrates preferred embodiments of the present invention, and that the present invention may be practiced without one or more of these details. Furthermore, to avoid confusion with the present invention, some technical features well known in the art have not been described in detail.

[0075] like Figures 1 to 3 As shown, the smoke guide pipe in the present invention is mainly used on the range hood and is arranged below the range hood box 200 so that the waste burned by the stove and the oil smoke generated during the cooking process that is harmful to the human body can be introduced into the range hood box 200 and exhausted to the outside. The smoke guide pipe is introduced in detail below with reference to the accompanying drawings.

[0076] The smoke guide pipe includes a first tube 110 and a second tube 120. The first tube 110 and the second tube 120 are connected to each other to form an outer tube wall 101 and an internal smoke guide channel 102. The outer tube wall 101 is the surface of the smoke guide pipe exposed to the outside, and the internal smoke guide channel 102 is connected to the fan cavity of the smoke machine box 200. A first driving transmission mechanism 130 is provided on the outer tube wall 101, which can make the first tube 110 swing relative to the second tube 120.

[0077] The above-mentioned smoke guide pipe is connected to the first tube 110 and the second tube 120, and the first drive transmission mechanism 130 is provided on the outer tube wall 101. It can not only swing left and right according to the position and size of the oil smoke to capture the oil smoke, but also reduce the impact of oil pollution on the first drive transmission mechanism 130, increase its service life, and facilitate the replacement operation of the first drive transmission mechanism 130.

[0078] See also Figure 4 The first tube 110 has a first end 1101 and a second end 1102. The first end 1101 has a smoking port 1103, so that the first end 1101 serves as the smoking end of the smoke guide tube. The second tube 120 has a connecting end 1201 opposite the second end 1102. The outer tube wall 101 includes a first outer tube wall 1011 located on the first tube 110 and a second outer tube wall 1012 located on the second tube 120. The first drive transmission mechanism 130 includes a first drive device 131, a first transmission member 132, and a first follower 133. The first drive device 131 is disposed on the first outer tube wall 1011 and has a first output shaft 1311. The first follower 133 is disposed on the connecting end 1201. The first output shaft 1311 is connected to the first follower 133 via the first transmission member 132 to drive the second tube 120. In this way, the first driving transmission mechanism 130 is simple and easy to assemble, thereby making production convenient and quick, and improving production efficiency.

[0079] In an embodiment not shown, the first drive device 131 may also be disposed on the second outer tube wall 1012 and include a first output shaft 1311. The first follower 133 is disposed on the second end 1102. The first output shaft 1311 is connected to the first follower 133 via the first transmission member 132 to drive the first tube 110. Such a first drive transmission mechanism 130 is also simple and easy to assemble, thereby facilitating rapid and convenient production and improving production efficiency.

[0080] As an exemplary embodiment, the first tube 110 includes a first inner tube 111 and a first outer tube 112. The first outer tube 112 is sleeved outside the first inner tube 111 and fixedly connected to the first inner tube 111. For example, the first outer tube 112 can be fixedly connected to the first inner tube 111 by a plurality of first connecting members 113. The first outer tube wall 1011 is the outer side surface of the first outer tube 112. The first outer tube 112 has a first connecting section 1121 at the second end 1102. The second tube 120 includes a second inner tube 121 and a second outer tube 122. The second outer tube 122 is sleeved outside the second inner tube 121 and fixedly connected to the second inner tube 121. For example, the second outer tube 122 can be fixedly connected to the second inner tube 121 by a plurality of second connecting members 123 (for example). Figure 7 (as shown), second outer tube wall 1012 forms the outer surface of second outer tube 122. Second outer tube 122 has a second connecting section 1221, which is connected to first connecting section 1121 via a bearing. Thus, second connecting section 1221 and first connecting section 1121 form a sealed connection between first tube 110 and second tube 120. This not only allows first tube 110 to swing smoothly relative to second tube 120, thereby facilitating accurate capture of oil smoke based on its location and size, but also prevents oil smoke from escaping from internal smoke guide channel 102 and affecting the service life of first drive transmission mechanism 130.

[0081] See again Figure 4 The first end 1101 is provided with a smoke hood 170, which includes a first hood body 171 extending downward and outward from the lower end of the first inner tube 111 and a second hood body 172 extending downward and outward from the lower end of the first outer tube 112. The second hood body 172 is disposed outside the first hood body 171. The smoke hood 170 can conveniently collect oil smoke and direct it into the internal smoke guide channel 102.

[0082] Furthermore, the smoke guide tube includes a third tube 140 having a third outer tube wall 1401. A second drive device 151 is disposed on the third outer tube wall 1401. The second drive device has a second output shaft 1511. The second tube 120 has a distal end 1202 distal from the first tube 110. A second follower 153 is disposed on the distal end 1202. The second output shaft 1511 is connected to the second follower 153 via a second transmission member 152 to drive the second tube 120. This allows the first tube 110 to swing relative to the second tube 120 while also causing the second tube 120 to swing relative to the third tube 140, thereby more accurately capturing oil smoke based on its location and size. It should be understood that the number of third tubes 140 can be adjusted according to actual needs. That is, the number of third tubes 140 can be one, two, or even more than two. A second driving device 151 is correspondingly provided on the third outer tube wall 1401 of each third tube 140. When there are two or more third tubes 140, part of the second driving device 151 is used to make the two connected third tubes 140 swing relative to each other.

[0083] See also Figure 5 The third tube 140 includes a third inner tube 141 and a third outer tube 142. The third outer tube 142 is sleeved outside the third inner tube 141 and fixedly connected to the third inner tube 141. For example, the third outer tube 142 can be fixedly connected to the third inner tube 141 via a plurality of third connecting members 143. The third outer tube 142 has a third connecting section 1421. The second outer tube 122 has a fourth connecting section 1222 that is separated from the second connecting section 1221. The third connecting section 1421 and the fourth connecting section 1222 are connected via a bearing. In this way, the third connecting section 1421 and the fourth connecting section 1222 form a sealed connection area between the third tube 140 and the second tube 120. This not only allows the third tube 140 to swing smoothly relative to the second tube 120, thereby facilitating accurate capture of oil smoke based on its location and size, but also prevents oil smoke from escaping from the internal smoke guide channel 102 and affecting the service life of the second drive device 151.

[0084] See also Figure 6 A mating surface 160 is formed between the first connecting section 1121 and the second connecting section 1221, and between the third connecting section 1421 and the fourth connecting section 1222. These surfaces are inclined at an angle α relative to the central axis of the second outer tube 122. These surfaces are elliptical with a major axis D1 and a minor axis D2, where D2 = D1 × cosα. This ensures relative swing between the first tube 110 and the second tube 120, and between the second tube 120 and the third tube 140, while also ensuring a tight connection between them, preventing smoke from escaping.

[0085] As an exemplary embodiment, D2 is 100 mm to 300 mm, and α is 15° to 35°. For example, D2 is 100 mm, 200 mm, 300 mm, etc., and α is 15°, 25°, 35°, etc. This can meet the smoke guide requirements of the range hood and can be well used in the range hood.

[0086] As an exemplary embodiment, the first drive device 131 is a motor, the first transmission member 132 is a first gear fixedly mounted on the first output shaft 1311, and the second outer tube 122 has a first outer edge surface 1223. The shape of the first outer edge surface 1223 is similar to that of the connecting mating surface 160. It should be noted that "similar" here refers to the same shape, but not necessarily the same size. Specifically, the shape of the first outer edge surface 1223 is also elliptical. The first driven member 133 is a second gear fixedly mounted on the first outer edge surface 1223 and meshing with the first gear. Thus, the gear transmission method between the first tube 110 and the second tube 120 is not only simple in structure but also easy to assemble.

[0087] As an exemplary embodiment, the second drive device 151 is a motor, the second transmission member 152 is a third gear fixedly mounted on the second output shaft 1511, and the second outer tube 122 has a second outer edge surface 1224. The shape of the second outer edge surface 1224 is similar to that of the connecting mating surface 160. It should be noted that "similar" here refers to the same shape, but not necessarily the same size. Specifically, the shape of the second outer edge surface 1224 is also elliptical. The second driven member 153 is a fourth gear fixedly mounted on the second outer edge surface 1224 and meshing with the third gear. In this way, the second and third tubes use a gear transmission method, which is not only simple in structure but also easy to assemble.

[0088] See also Figures 7 to 9 The first inner tube 111 has a first chute 1111 at its second end 1102, and the second inner tube 121 has a first connecting portion 1211 that extends into the first chute 1111. This prevents unnecessary interference between the first tube 110 and the second tube 120 during relative rotation. In an embodiment not shown, the second inner tube 121 may also have a first chute, and the first inner tube 111 may have a first connecting portion at its second end 1102 that extends into the first chute.

[0089] The connection between the third inner tube 141 and the second inner tube 121 is similar to the connection between the first inner tube 111 and the second inner tube 121. That is, the third inner tube 141 has an inner tube connecting end (not shown) connected to the second inner tube 121, the inner tube connecting end having a second chute (not shown), and the second inner tube 121 has a second connecting portion 1212 extending into the second chute. This prevents unnecessary interference between the second tube 120 and the third tube 140 during relative rotation. In an embodiment not shown, the second inner tube 121 can also have an inner tube connecting end connected to the third inner tube 141, the inner tube connecting end having a second chute, and the third inner tube 141 having a second connecting portion extending into the second chute.

[0090] According to another aspect of the present invention, a range hood is provided, comprising a range hood housing 200 and a smoke duct disposed below the range hood housing 200. The smoke duct is the aforementioned smoke duct. In addition, the range hood housing 200 may include a fan and other components. The fan and other components may have various existing or future structures, and these structures do not limit the scope of protection of the present invention. Since the aforementioned smoke duct has the aforementioned beneficial effects, a range hood including such a smoke duct will also necessarily have the aforementioned beneficial effects.

[0091] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "below", "inside" and "outside" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside" and "outside" refer to the inside and outside relative to the outline of each component itself.

[0092] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship between one or more components or features shown in the figures and other components or features. It should be understood that spatially relative terms include not only the orientation of the components as described in the figures, but also different orientations during use or operation. For example, if the components in the drawings are inverted as a whole, the situation where the components are "above other components or features" or "above other components or features" will include the situation where the components are "below other components or structures" or "below other components or structures". Thus, the exemplary term "above" may include both the orientations "above" and "below". In addition, these components or features may also be positioned at other different angles (e.g., swung 90 degrees or other angles), and this document is intended to include all of these situations.

[0093] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, parts, components and / or combinations thereof.

[0094] The present invention has been described through the above-described embodiments. However, it should be understood that the above-described embodiments are for illustrative and illustrative purposes only and are not intended to limit the present invention to the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments and that various variations and modifications may be made based on the teachings of the present invention, all of which fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A smoke guide pipe, comprising a first pipe and a second pipe, wherein the first pipe and the second pipe are connected to form an outer pipe wall and an inner smoke guide channel, characterized in that: A first driving transmission mechanism is provided on the outer tube wall surface, which is capable of causing the first tube to swing relative to the second tube; In which, the first tube has a first end and a second end, the first end has a smoking port, the second tube has a connecting end opposite to the second end, the first tube includes a first inner tube and a first outer tube, the first outer tube is sleeved outside the first inner tube and fixedly connected to the first inner tube, and the first outer tube has a first connecting section at the second end; the second tube includes a second inner tube and a second outer tube, the second outer tube is sleeved outside the second inner tube and fixedly connected to the second inner tube, and the second outer tube has a second connecting section; the second connecting section is connected to the first connecting section via a bearing.

2. The smoke guide tube according to claim 1, characterized in that: The outer tube wall surface includes a first outer tube wall surface located on the first outer tube and a second outer tube wall surface located on the second outer tube. The first drive transmission mechanism includes a first drive device, a first transmission member and a first follower. The first drive device is arranged on the first outer tube wall surface and has a first output shaft. The first follower is arranged on the connecting end. The first output shaft is connected to the first follower through the first transmission member so as to be able to drive the second tube; or, the first drive device is arranged on the second outer tube wall surface and has a first output shaft. The first follower is arranged on the second end. The first output shaft is connected to the first follower through the first transmission member so as to be able to drive the first tube.

3. The smoke guide tube according to claim 2, characterized in that: The smoke guide pipe also includes a third tube, the third tube has a third outer tube wall, a second driving device is provided on the third outer tube wall, the second driving device has a second output shaft, the second tube has a remote end away from the first tube, the remote end has a second follower, the second output shaft is connected to the second follower through a second transmission member so as to be able to drive the second tube.

4. The smoke guide tube according to claim 3, characterized in that: The third tube includes a third inner tube and a third outer tube. The third outer tube is sleeved outside the third inner tube and fixedly connected to the third inner tube. The third outer tube has a third connecting section. The second outer tube has a fourth connecting section away from the second connecting section. The third connecting section and the fourth connecting section are connected by a bearing.

5. The smoke guide tube according to claim 4, characterized in that: A connecting mating surface is formed between the first connecting segment and the second connecting segment, and between the third connecting segment and the fourth connecting segment. The connecting mating surface has an inclination angle α relative to the central axis of the second outer tube, and is an ellipse with a major axis D1 and a minor axis D2, wherein D2=D1×cosα.

6. The smoke guide tube according to claim 5, characterized in that: D2 is 100mm~300mm, and α is 15°~35°.

7. The smoke guide tube according to claim 5, characterized in that: The first driving device is a motor, the first transmission member is a first gear fixedly provided on the first output shaft, the second outer tube has a first outer edge surface, the shape of the first outer edge surface is similar to the shape of the connecting mating surface, and the first follower is a second gear fixedly provided on the first outer edge surface and meshing with the first gear.

8. The smoke guide tube according to claim 5, characterized in that: The second driving device is a motor, the second transmission member is a third gear fixedly provided on the second output shaft, the second outer tube has a second outer edge surface, the shape of the second outer edge surface is similar to the shape of the connecting mating surface, and the second follower is a fourth gear fixedly provided on the second outer edge surface and meshing with the third gear.

9. The smoke guide tube according to any one of claims 1 to 8, characterized in that: The first inner tube has a first chute at the second end, and the second inner tube has a first connecting portion extending into the first chute; or the second inner tube has a first chute, and the first inner tube has a first connecting portion extending into the first chute at the second end.

10. The smoke guide tube according to any one of claims 4 to 8, characterized in that: The third inner tube has an inner tube connecting end connected to the second inner tube, the inner tube connecting end has a second slide groove, and the second inner tube has a second connecting portion extending into the second slide groove; or the second inner tube has an inner tube connecting end connected to the third inner tube, the inner tube connecting end has a second slide groove, and the third inner tube has a second connecting portion extending into the second slide groove.

11. A range hood comprising a range hood box and a smoke guide pipe arranged below the range hood box, characterized in that: The smoke guide pipe is the smoke guide pipe according to any one of claims 1 to 10.

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