Push rod assembly and range hood

Abstract

The utility model provides a push rod assembly and a range hood, the push rod assembly comprises a first rod, a second rod, a stopper and an oil-proof member, the second rod is sleeved outside the first rod, the first rod is slidably connected to the second rod and can be extended or retracted relative to the second rod; the stopper is connected to the second rod, and a limited position space is formed between the stopper and the end of the second rod; the oil-proof member is sleeved on the first rod and is limited in the limited position; wherein, when the first rod is retracted relative to the second rod, the oil-proof member moves with the first rod and is stopped at the first position by the end of the second rod, and the oil-proof member at least partially covers the gap between the first rod and the second rod; when the first rod is extended relative to the second rod, the oil-proof member moves with the first rod and is stopped at the second position by the stopper. In the push rod assembly of the utility model, when the first rod is retracted, the oil stains on the first rod will not enter the inside of the second rod from the gap between the first rod and the second rod under the action of the oil-proof member, thereby achieving the oil-proof effect.

Description

Technical Field

[0001] The utility model relates to the technical field of range hoods, in particular to a push rod assembly and a range hood. Background Art

[0002] Most of the current range hoods use a push rod assembly to push and pull the smoke shield. When the push rod assembly pushes open the smoke shield, the inner push rod is extended and exposed to the smoke, and a layer of oil will be attached to the extended section of the inner push rod. After the range hood is used up and the inner push rod is retracted, a portion of the oil attached to the inner push rod will remain inside the outer push rod. Over time, the oil inside the outer push rod accumulates more and more, and the oil condenses into solid oil after cooling, which directly affects the friction between the inner push rod and the outer push rod, resulting in the need to increase the driving force during the extension and retraction of the inner push rod. This means that when a driving member is used to drive the inner push rod to extend and retract, the service life of the driving member will be reduced. Utility Model Content

[0003] In order to at least partially solve the problems existing in the prior art, according to one aspect of the utility model, a push rod assembly is provided, and the technical solution is as follows.

[0004] The push rod assembly includes a first rod, a second rod, a limit piece and an oil-proof piece. The second rod is sleeved outside the first rod, and the first rod is slidably connected to the second rod and can be extended or retracted relative to the second rod; the limit piece is connected to the second rod, and a limited space is formed between the limit piece and the end of the second rod; the oil-proof piece is sleeved on the first rod and confined in the limited space; wherein, when the first rod is retracted relative to the second rod, the oil-proof piece moves with the first rod and is stopped at the first position by the end of the second rod, and the oil-proof piece at least partially covers the gap between the first rod and the second rod; when the first rod is extended relative to the second rod, the oil-proof piece moves with the first rod and is stopped at the second position by the limit piece.

[0005] The push rod assembly of the utility model is provided with a limit piece and an oil-proof piece. When the first rod is retracted relative to the second rod, the oil-proof piece blocks and stops by the end portion of the second rod, and the oil-proof piece at least partially covers the gap between the first rod and the second rod. Therefore, when the first rod is retracted, the oil stains on the first rod will not enter the inside of the second rod from the gap between the first rod and the second rod under the action of the oil-proof piece, thereby achieving the oil-proof effect and avoiding the influence of the friction force between the first rod and the second rod. At the same time, the oil-proof piece is limited by the limit piece to avoid the oil-proof piece moving a large distance with the first rod and falling off when the first rod is retracted, thereby affecting the oil-proof effect.

[0006] For example, the oil-proof member has a first through hole, and the oil-proof member is sleeved on the first rod through the first through hole, and the first rod and the first through hole are interference-fitted. Such a configuration has a good oil-proof effect, and avoids the formation of a gap between the first rod and the oil-proof member, which causes oil to flow from the gap into the gap between the first rod and the second rod.

[0007] Exemplarily, the second rod has an annular wall, the oil-proof member has a first annular portion and a second annular portion, the first annular portion and the second annular portion are sequentially arranged from the first through hole in a radial direction outward, and when the oil-proof member is in the first position, the first annular portion covers the gap between the first rod and the second rod, and the second annular portion abuts against the annular wall. In this arrangement, the first annular portion covers the gap between the first rod and the second rod, and the second annular portion abuts against the annular wall, thereby achieving an oil-proof effect, and avoiding the phenomenon that the oil-proof member cannot cover the gap between the first rod and the second rod, causing oil to flow into the second rod.

[0008] For example, there is a tolerance δ between the aperture of the first through hole and the outer diameter of the first rod, and the tolerance δ is -0.15mm to -0.2mm. This arrangement can avoid the tolerance δ being too large, causing a gap between the oil-proof member and the first rod, affecting the oil-proof effect, and can also avoid the tolerance δ being too small, affecting the assembly of the oil-proof member and the first rod.

[0009] Exemplarily, the limiting member has a limiting portion, a transition portion, and a connecting portion. The limiting portion is perpendicular to the axial direction of the first rod, and the oil-proof member stops at the second position when it moves to abut against the limiting portion; the connecting portion is connected to the end of the second rod through a fastener; and the transition portion is connected between the limiting portion and the connecting portion. In this arrangement, since the oil-proof member moves along the axial direction of the first rod with the first rod, the limiting portion is perpendicular to the axial direction of the first rod to facilitate the limiting of the oil-proof member; the connecting portion is connected to the end of the second rod through a fastener, which facilitates the connection between the limiting member and the second rod, and makes the limiting member and the second rod have a high degree of firmness, which can limit the oil-proof member to stop at the second position; the limiting portion and the connecting portion are connected by the transition portion to form a limiting space between the limiting portion and the end of the second rod, which facilitates the movement of the oil-proof member in the limiting space.

[0010] Exemplarily, there is a spacing length L between the limiting portion and the end of the second rod to form a limiting space, and in the axial direction of the first rod, the oil-proof member has a thickness H, and LH is 0 mm to 0.5 mm. LH is the moving distance of the oil-proof member. Within this range, the moving distance of the oil-proof member has an oil-proof effect compared to the oil-proof member being in an extruded state, and does not affect the extension or retraction efficiency of the first rod.

[0011] Exemplarily, the limiting part is provided with a second through hole, and the limiting part is sleeved on the first rod through the second through hole. With such a configuration, the limiting part has better stability and is convenient for limiting the oil-proof part.

[0012] Exemplarily, the adapter has a first end and a second end, the first end is connected to the connecting portion, the second end is connected to the limiting portion, and the hole wall of the second through hole is provided with a notch, the notch extends away from the center of the second through hole and extends through the first end to the second end to form a slot. In this way, the head end of the fastener connecting the second rod end and the connecting portion is given space through the slot, which reduces wear and facilitates assembly.

[0013] Exemplarily, the first rod is connected to a driving member, and the first rod can be extended or retracted relative to the second rod along the axial direction of the second rod through the driving member. The driving member is provided to facilitate the movement of the first rod relative to the second rod, thereby achieving automation and avoiding the need for users to manually pull out or push back the first rod.

[0014] According to another aspect of the utility model, a range hood is provided, comprising a smoke baffle and the push rod assembly as described above, wherein one end of the first rod away from the second rod is connected to the smoke baffle. Since the push rod assembly as described above has the above beneficial effects, the range hood comprising the push rod assembly as described above also has the above beneficial effects, which will not be described one by one here.

[0015] A series of simplified concepts are introduced in the utility model content, which will be further described in detail in the detailed implementation section. The utility model content section does not mean to attempt to define the key features and essential technical features of the technical solution claimed for protection, nor does it mean to attempt to determine the scope of protection of the technical solution claimed for protection.

[0016] The advantages and features of the present invention are described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following drawings of the present invention are used as part of the present invention for understanding the present invention. The drawings show the implementation of the present invention and its description, and are used to explain the principle of the present invention. In the drawings,

[0018] Figure 1 A three-dimensional diagram of a range hood according to an exemplary embodiment of the present invention;

[0019] Figure 2 for Figure 1 A front view of the range hood shown;

[0020] Figure 3 for Figure 2 AA section view in;

[0021] Figure 4 for Figure 1 A perspective view of the push rod assembly shown;

[0022] Figure 5 for Figure 4 Enlarged view of the middle part I;

[0023] Figure 6 for Figure 4 A partial exploded view of

[0024] Figure 7 for Figure 4 A front view of the push rod assembly is shown;

[0025] Figure 8 for Figure 4 The state of the push rod assembly shown is referenced Figure 1 ;

[0026] Fig. 9 for Figure 4 The state of the push rod assembly shown is referenced Figure 2 ;

[0027] Fig.10 for Figure 4 a right side view of the first push rod shown;

[0028] Fig.11 for Figure 4 Right side view of the oil guard shown.

[0029] The above drawings include the following reference numerals:

[0030] 1. Range hood; 10. Push rod assembly; 110. First rod; 120. Second rod; 121. Annular wall; 130. Stopper; 131. Stopper portion; 1311. Second through hole; 1312. Notch; 132. Adapter portion; 1321. First end; 1322. Second end; 133. Connector portion; 134. Slot; 140. Oil-proof member; 141. First through hole; 142. First annular portion; 143. Second annular portion; 150. Stopper space; 160. Fastener; 170. Drive member; 20. Smoke baffle; D1. Diameter of the first through hole; D2. Outer diameter of the first rod. DETAILED DESCRIPTION

[0031] In the following description, a large number of details are provided so that the present invention can be thoroughly understood. However, it will be appreciated by those skilled in the art that the following description only illustrates preferred embodiments of the present invention, and the present invention can be implemented without one or more of such details. In addition, in order to avoid confusion with the present invention, some technical features known in the art are not described in detail.

[0032] In order to thoroughly understand the implementation of the utility model, a detailed structure will be presented in the following description. Obviously, the implementation of the utility model is not limited to the specific details familiar to those skilled in the art. The preferred implementation of the utility model is described in detail below, but in addition to these detailed descriptions, the utility model can also have other implementations.

[0033] The embodiment of the utility model provides a push rod assembly. The push rod assembly provided by the utility model can be applied to, but not limited to, a range hood. The following will introduce a push rod assembly according to the embodiment of the utility model in detail in conjunction with the accompanying drawings.

[0034] Combined with reference Figure 4 , Figure 5 , Figure 8 and Fig. 9 , the push rod assembly 10 may include a first rod 110, a second rod 120, a limiter 130 and an oil-proof member 140. The second rod 120 may be sleeved outside the first rod 110. The first rod 110 and the second rod 120 are slidably connected and can be extended or retracted relative to the second rod 120. The limiter 130 may be connected to the second rod 120, and a limited space 150 may be formed between the limiter 130 and the end of the second rod 120. The oil-proof member 140 may be sleeved on the first rod 110 and confined in the limited space 150. Among them, when the first rod 110 retracts relative to the second rod 120, the oil-proof member 140 may move with the first rod 110 and be blocked by the end of the second rod 120 and stop at the first position (such as Figure 8 As shown, the oil-proof member 140 is in the first position at this time). At least a portion of the oil-proof member 140 can cover the gap between the first rod 110 and the second rod 120. When the first rod 110 extends relative to the second rod 120, the oil-proof member 140 can move with the first rod 110 and stop at the second position (as shown in FIG. Fig. 9 As shown, the oil-proof member 140 is at the first position at this time). It can be understood that the oil-proof member 140 is movable relative to the first rod 110.

[0035] The push rod assembly 10 of the utility model is provided with a limit member 130 and an oil-proof member 140. When the first rod 110 retracts relative to the second rod 120, the oil-proof member 140 blocks and stops by the end of the second rod 120. The oil-proof member 140 at least partially covers the gap between the first rod 110 and the second rod 120. Therefore, when the first rod 110 retracts, the oil stains on the first rod 110 will not enter the inside of the second rod 120 from the gap between the first rod 110 and the second rod 120 under the action of the oil-proof member 140, thereby achieving the oil-proof effect and avoiding the influence of the friction between the first rod 110 and the second rod 120. At the same time, the oil-proof member 140 is limited by the limit member 130 to avoid the oil-proof member 140 moving a large distance with the first rod 110 and falling off when the first rod 110 retracts, thereby affecting the oil-proof effect.

[0036] Furthermore, since the oil-proof member 140 needs to be sleeved on the first rod 110, for the convenience of assembly, the shape of the oil-proof member 140 can be similar to or consistent with the shape of the first rod 110. The shape of the first rod 110 can be various, for example, the shape of the first rod 110 can be cylindrical or square. When the shape of the first rod 110 is cylindrical, the shape of the oil-proof member 140 can be annular. The oil-proof member 140 can be made of an oil-resistant elastic material, such as nitrile rubber.

[0037] Specifically, when the first rod 110 is extended, the oil-proof component 140 will first move along the axial direction of the first rod 110 with the first rod 110. Under the action of the limit member 130 on the oil-proof component 140 in the opposite direction of the axis of the first rod 110, the oil-proof component 140 will be blocked and stopped at the second position.

[0038] Combined with reference Figure 7 and Fig.11 , the oil-proof member 140 may have a first through hole 141. The oil-proof member 140 may be sleeved on the first rod 110 through the first through hole 141, and the first rod 110 and the first through hole 141 may be interference fit. Such a configuration has a good oil-proof effect, and avoids the generation of a gap between the first rod 110 and the oil-proof member 140, resulting in oil dirt flowing from the gap into the gap between the first rod 110 and the second rod 120. Further, the first rod 110 may have different sizes. In order to meet the interference fit between the oil-proof member 140 and the first rod 110, the oil-proof member 140 may be a sealing ring, and the sealing size of the sealing ring may be slightly smaller than the first rod 110.

[0039] Combined with reference Figure 6 , Figure 8 and Fig.11, the second rod 120 may have an annular wall 121. The annular wall 121 may be located at one end of the second rod 120 close to the first rod 110. The oil-proof member 140 may have a first annular portion 142 and a second annular portion 143. The first annular portion 142 and the second annular portion 143 may be sequentially arranged from the first through hole 141 in a radial direction outward. When the oil-proof member 140 is located in the first position, the first annular portion 142 may cover the gap between the first rod 110 and the second rod 120, and the second annular portion 143 may abut against the annular wall 121. In this arrangement, the first annular portion 142 covers the gap between the first rod 110 and the second rod 120, and the second annular portion 143 abuts against the annular wall 121, thereby achieving an oil-proof effect, and avoiding the phenomenon that the oil-proof member 140 cannot cover the gap between the first rod 110 and the second rod 120, causing oil to flow into the interior of the second rod 120.

[0040] Combined with reference Figure 7 , Fig.10 and Fig.11 , there may be a tolerance δ between the aperture D1 of the first through hole 141 and the outer diameter D2 of the first rod 110, and the tolerance δ may be -0.15mm to -0.2mm. For example, the tolerance δ may be -0.15mm, -0.17mm, -0.2mm, and the tolerance δ is preferably -0.17mm. This arrangement avoids a too large tolerance δ, which may cause a gap between the oil-proof member 140 and the first rod 110 and affect the oil-proof effect, and avoids a too small tolerance δ, which may affect the assembly of the oil-proof member 140 and the first rod 110. It can be understood that the aperture D1 of the first through hole - the outer diameter D2 of the first rod = the tolerance δ.

[0041] Combined with reference Figure 6 and Fig. 9The limiting member 130 may include a limiting portion 131, a transition portion 132, and a connecting portion 133. The limiting portion 131 may be perpendicular to the axial direction of the first rod 110. The oil-proof member 140 may move to abut against the limiting portion 131 and stop at the second position. The connecting portion 133 may be connected to the end of the second rod 120 by a fastener 160. The transition portion 132 may be connected between the limiting portion 131 and the connecting portion 133. In this configuration, since the oil-proof member 140 moves along the axial direction of the first rod 110 with the first rod 110, the limiting portion 131 is perpendicular to the axial direction of the first rod 110 to facilitate limiting the oil-proof member 140; the connecting portion 133 is connected to the end of the second rod 120 through a fastener, which facilitates the connection between the limiting member 130 and the second rod 120, and makes the limiting member 130 and the second rod 120 have a high degree of firmness, and can limit the oil-proof member 140 to stop at the second position; the limiting portion 131 and the connecting portion 133 are connected through the adapter 132 to form a limiting space 150 between the limiting portion 131 and the end of the second rod 120, so as to prevent the oil-proof member 140 from affecting the efficiency of pushing out the first rod 110. It can be understood that the limiting member 130 is detachable relative to the second rod 120 through the fastener 160. Further, the limiting member 130 can be a sheet metal part, and of course it is not excluded that the limiting member 130 can be a part of other forms. The fastener 160 may be a screw or a bolt, etc.

[0042] Combined with reference Figures 7 to 9 , there may be a spacing length L between the limiting portion 131 and the end of the second rod 120 to form a limiting space 150. In the axial direction of the first rod 110, the oil-proof member 140 may have a thickness H, and LH may be 0 mm to 0.5 mm. For example, LH may be 0 mm, 0.25 mm, or 0.5 mm. When LH is 0 mm, the oil-proof member 140 abuts against the end of the second rod 120, and the oil-proofing effect of the oil-proof member 140 is the best. LH is the moving distance of the oil-proof member 140. When the moving distance of the oil-proof member 140 is within this range, compared with the oil-proof member 140 being in an extruded state, it has an oil-proofing effect and does not affect the extension or retraction efficiency of the first rod 110.

[0043] Again, refer to Figure 6 and Fig. 9 The limiting portion 131 may be provided with a second through hole 1311, and the limiting portion 131 may be sleeved on the first rod 110 through the second through hole 1311. In this way, the limiting portion 131 has better stability and is convenient for limiting the oil-proof member 140. Furthermore, the diameter of the second through hole 1311 may be smaller than the outer diameter of the oil-proof member 140 in the direction perpendicular to the axial direction of the first rod 110, so as to prevent the oil-proof member 140 from passing through the second through hole 1311 and failing to play a limiting role.

[0044] See also Figure 6, the adapter portion 132 may have a first end 1321 and a second end 1322. The first end 1321 may be connected to the connecting portion 133, and the second end 1322 may be connected to the limiting portion 131. The hole wall of the second through hole 1311 may be provided with a notch 1312, and the notch 1312 may extend in a direction away from the center of the second through hole 1311 and extend through the first end 1321 to the second end 1322 to form a slot 134. In this way, the slot 134 gives way to the head end of the fastener 160 connecting the end of the second rod 120 and the connecting portion 133, thereby reducing wear and facilitating assembly. Specifically, after the connecting portion 133 is aligned with the end of the second rod 120, since the head end of the screw is larger than the diameter of the screw thread end, and the position space where the limiting member 130 is connected to the second rod 120 is small, the screw can smoothly connect the connecting portion 133 with the end of the second rod 120 by giving way to the head end of the screw through the slot 134.

[0045] See also Figure 4 , the first rod 110 may be connected to a driving member 170. The first rod 110 may be extended or retracted relative to the second rod 120 along the axial direction of the second rod 120 by the driving member 170. The driving member 170 facilitates the movement of the first rod 110 relative to the second rod 120, realizes automation, and avoids the user from manually dragging out or pushing back the first rod 110. The driving member 170 may be a motor or a cylinder, etc. The driving member 170 may be arranged perpendicular to the axial direction of the second rod 120. Of course, the situation in which the driving member 170 is arranged along the axial direction of the second rod 120 is not excluded. It should be noted that the axial direction of the second rod 120 is the same as the axial direction of the first rod 110.

[0046] Further, see Figure 8 and Fig. 9 , the driving member 170 drives the first rod 110 to extend relative to the second rod 120 along the axial direction of the second rod 120 to a third position, at which time the first rod 110 is in an extended state. The push rod assembly 10 may have a length S1, which may be 229 mm to 230 mm, for example, the length S1 may be 229 mm, 229.5 mm, 230 mm, and the length S1 is preferably 229.5 mm. The driving member 170 drives the first rod 110 to retract relative to the second rod 120 along the axial direction of the second rod 120 to a fourth position, at which time the first rod 110 is in a retracted state. The push rod assembly 10 may have a length S2, which may be 169 mm to 170 mm, for example, the length S2 may be 169 mm, 169.5 mm, 170 mm, and the length S2 is preferably 169.5 mm.

[0047] According to another aspect of the present invention, a range hood 1 is provided. Figures 1 to 11The range hood 1 includes a smoke damper 20 and the push rod assembly 10 as described above, and one end of the first rod 110 away from the second rod 120 is connected to the smoke damper 20. Since the push rod assembly 10 as described above has the above-mentioned beneficial effects, the range hood 1 including the push rod assembly 10 as described above also has the above-mentioned beneficial effects, which will not be described one by one here. Specifically, when the first rod 110 is extended, the smoke damper 20 is pushed out until the first rod 110 is in the extended state, and the smoke damper 20 is in the open state. When the first rod 110 is retracted, the smoke damper 20 is pulled back until the first rod 110 is in the retracted state, and the smoke damper 20 is in the closed state.

[0048] The operation process of the push rod assembly 10 and the smoke baffle 20 in the range hood 1 is described below. When the user starts the range hood 1, the driving member 170 drives the first rod 110 to extend relative to the second rod 120, and pushes out the smoke baffle 20 until the smoke baffle 20 is in an open state, and the oil-proof member 140 moves with the first rod 110 and is limited to the second position by the limiting member 130; when the user turns off the range hood 1, the driving member 170 drives the first rod 110 to retract relative to the second rod 120, and pulls back the smoke baffle 20 until the smoke baffle 20 is in a closed state, and the oil-proof member 140 moves with the first rod 110 and abuts against the end of the second rod 120 and stops at the first position, and the oil-proof member 140 filters the oil out of the second rod 120.

[0049] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front", "back", "up", "down", "left", "right", "lateral", "vertical", "vertical", "horizontal", "top", "bottom", etc. are usually based on the directions or positional relationships shown in the drawings, and 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, and therefore 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 contours of each component itself.

[0050] For ease of description, regional relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the regional positional relationship between one or more components or features shown in the figure and other components or features. It should be understood that regional relative terms include not only the orientation of the components as described in the figure, but also different orientations in use or operation. For example, if the components in the accompanying drawings are inverted as a whole, the components "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". Therefore, the exemplary term "above" may include both "above" and "below". In addition, these components or features may also be positioned at other different angles (e.g., rotated 90 degrees or other angles), and this article is intended to include all of these situations.

[0051] 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, it indicates the presence of features, steps, operations, parts, components and / or combinations thereof.

[0052] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0053] The utility model has been described through the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the utility model to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the utility model is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the utility model, and these variations and modifications all fall within the scope of protection claimed by the utility model. The protection scope of the utility model is defined by the attached claims and their equivalents.

Claims

1. A push rod assembly, characterized in that: It comprises a first rod, a second rod, a stopper and an oil-proof member, wherein the second rod is sleeved outside the first rod, and the first rod is slidably connected to the second rod and can be extended or retracted relative to the second rod; The limiting member is connected to the second rod, and a limiting space is formed between the limiting member and the end of the second rod; The oil-proof member is sleeved on the first rod and is confined within the limiting space; Wherein, when the first rod is retracted relative to the second rod, the oil-proof component moves with the first rod and is stopped at the first position by the end of the second rod, and the oil-proof component at least partially covers the gap between the first rod and the second rod; when the first rod is extended relative to the second rod, the oil-proof component moves with the first rod and is stopped at the second position by the limit component.

2. The push rod assembly according to claim 1, characterized in that: The oil-proof component has a first through hole. The oil-proof component is sleeved on the first rod through the first through hole, and the first rod and the first through hole are interference-fitted.

3. The push rod assembly according to claim 2, characterized in that: The second rod has an annular wall, and the oil-proof member has a first annular portion and a second annular portion. The first annular portion and the second annular portion are sequentially arranged outward from the first through hole in a radial direction. When the oil-proof member is located at the first position, the first annular portion covers the gap between the first rod and the second rod, and the second annular portion abuts against the annular wall.

4. The push rod assembly according to claim 2, characterized in that: A tolerance δ exists between the hole diameter of the first through hole and the outer diameter of the first rod, and the tolerance δ is -0.15 mm to -0.2 mm.

5. The push rod assembly according to claim 2, characterized in that: The limiting component comprises a limiting portion, a transition portion and a connecting portion, the limiting portion is perpendicular to the axial direction of the first rod, and the oil-proof component stops at the second position when it moves to abut against the limiting portion; the connecting portion is connected to the end of the second rod through a fastener; and the transition portion is connected between the limiting portion and the connecting portion.

6. The push rod assembly according to claim 5, characterized in that: There is a spacing length L between the limiting portion and the end of the second rod to form the limiting space. In the axial direction of the first rod, the oil-proof member has a thickness H, and LH is 0 mm to 0.5 mm.

7. The push rod assembly according to claim 5, characterized in that: The limiting portion is provided with a second through hole, and the limiting portion is sleeved on the first rod through the second through hole.

8. The push rod assembly according to claim 7, characterized in that: The transition portion has a first end and a second end, the first end is connected to the connecting portion, the second end is connected to the limiting portion, and a notch is provided on the hole wall of the second through hole, the notch extends away from the center direction of the second through hole and extends through the first end to the second end to form a groove.

9. The push rod assembly according to any one of claims 1 to 8, characterized in that: The first rod is connected to a driving member, and the first rod can be extended or retracted relative to the second rod along the axial direction of the second rod through the driving member.

10. A range hood, characterized in that: The utility model comprises a smoke baffle and a push rod assembly according to any one of claims 1 to 9, wherein one end of the first rod away from the second rod is connected to the smoke baffle.

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