Grass trimmer

Abstract

The utility model provides a grass trimmer, comprising: a housing in which a motor is arranged; the working head is driven by the motor to rotate; the spacing piece is used for spacing the shell and the working head and is positioned between the shell and the working head; the grass trimmer comprises a shell and a spacer, an assembly gap is formed between the spacer and the shell in the direction of an output shaft of the motor, the grass trimmer comprises a first blocking structure, and the first blocking structure is arranged around the output shaft of the motor and used for shielding or hiding the assembly gap; the grass trimmer further comprises a second blocking structure, and the second blocking structure surrounds the first blocking structure and is used for shielding or hiding the assembling gap. By arranging the first blocking structure and the second blocking structure, sundries are prevented from entering the grass trimmer, and the use reliability of the grass trimmer is improved.

Description

Technical Field

[0001] The present application relates to the technical field of tools, and in particular to a grass trimmer. Background Art

[0002] During the operation of the lawn mower, flying grass clippings, sand, gravel and other debris will enter the gaps of the lawn mower. The debris will accumulate in the gaps for a long time and affect the normal use of the lawn mower.

[0003] A lawn mower usually includes a motor and a working head, as well as a partition or fan located between the motor and the working head. In the prior art, the outer wall of the partition or the fan and the outer wall of the motor housing are usually used to cooperate to prevent debris from entering the gap between the partition or the fan and the motor. However, the protective effect is limited, and debris may still enter positions such as bearings or output shafts, affecting the life of the entire machine, making the lawn mower less reliable. Utility Model Content

[0004] In view of this, the purpose of the present application is to provide a lawn mower that solves the problem of debris entering the interior of the lawn mower and affecting the service life of the lawn mower, thereby increasing the reliability of the lawn mower.

[0005] Based on the above-mentioned purpose, the present application provides an electric tool, comprising: a shell, in which a motor is arranged; a working head, which rotates under the drive of the motor; a spacer, which is used to separate the shell and the working head and is located between the shell and the working head; and an assembly gap is provided between the spacer and the shell along the direction of the output shaft of the motor. The lawn mower comprises a first blocking structure, which is arranged around the output shaft of the motor and is used to shield or mask the assembly gap; the lawn mower comprises a second blocking structure, which is arranged around the first blocking structure and is used to shield or mask the assembly gap.

[0006] Optionally, the first blocking structure includes: an inner ring portion, which is located on the spacer and is arranged around the output shaft of the motor; a first protrusion portion, which protrudes from the shell and covers the inner ring portion, and the relative surfaces of the inner ring portion and the first protrusion portion are at least partially covered.

[0007] Optionally, the grass trimmer further includes: a bearing, wherein the bearing is sleeved on the output shaft; and the first protrusion is arranged around the bearing.

[0008] Optionally, the second blocking structure includes: an outer edge portion, which is located on the spacer and is arranged around the first blocking structure; a second protrusion portion, which protrudes from the shell and covers the outer edge portion, and the outer edge portion and the second protrusion portion at least partially cover the opposite surfaces.

[0009] Optionally, the spacer is a fan, comprising: blades; connecting ribs, the connecting ribs are arranged around the output shaft of the motor, and one end of a plurality of blades are arranged around the connecting ribs; the axial height of the blades is smaller than the axial height of the connecting ribs, so that there is a gap between the blades and the working head.

[0010] Optionally, the axial height of the blade is a, and the axial height of the connecting rib is b; wherein 0.1mm≤ba≤0.3mm.

[0011] Optionally, the fan comprises: a positioning hole, the positioning hole being used to accommodate a positioning pin, and the positioning hole being configured so that after the positioning pin passes through the positioning hole, an angle greater than 0 degrees is formed between the axis of the positioning pin and the axis of the fan.

[0012] Optionally, the positioning hole includes: a convex rib, and the convex rib surrounds the opening of the positioning hole.

[0013] Optionally, the spacer is a fan, and the shell is provided with: a heat dissipation port, which is located on the side of the shell facing the fan; the fan comprises a plurality of blades, and a heat dissipation duct is formed between adjacent blades; at least part of the heat dissipation port and the heat dissipation duct are located on the same ventilation path.

[0014] Optionally, the heat dissipation openings are evenly distributed around the axis of the motor.

[0015] As can be seen from the above, the lawn mower provided in the present application is provided with a first blocking structure to block the assembly gap between the fan and the casing, and is also provided with a second blocking structure to block the assembly gap, and the second blocking structure surrounds the first blocking structure. When debris enters the lawn mower, it is blocked by the first blocking structure and the second blocking structure at two levels, thereby effectively preventing the entry of debris and improving the service life of the lawn mower. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 is a structural diagram of a grass trimmer in one embodiment of the present application;

[0018] Figure 2 A partial exploded view of a lawn mower in one embodiment of the present application;

[0019] Figure 3A partial cross-sectional view of a grass trimmer in one embodiment of the present application;

[0020] Figure 4 for Figure 3 Detailed view of point A in the middle;

[0021] Figure 5 is a partial cross-sectional view of a grass trimmer in another embodiment of the present application;

[0022] Figure 6 is a structural diagram of a housing in one embodiment of the present application;

[0023] Figure 7 The structure of the fan in one embodiment of the present application Figure 1 ;

[0024] Figure 8 The structure of the fan in one embodiment of the present application Figure 2 .

[0025] Reference numerals:

[0026] 1. Grass trimmer; 101. Operating handle; 102. Operating tube; 100. Motor; 110. Output shaft; 200. Working head; 210. Blade; 300. Spacer; 310. Inner ring; 320. Outer edge; 330. Blade; 340. Connecting rib; 350. Positioning hole; 360. Cooling duct; 301. Fan; 302. Partition; 400. First assembly gap; 500. Second assembly gap; 600. Shell; 610. First raised portion; 620. Second raised portion; 630. Cooling port; 700. Bearing. DETAILED DESCRIPTION

[0027] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0028] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0029] like Figure 1 As shown, the lawn mower 1 is a tool for mowing lawns, vegetation, etc., and generally includes a battery pack, an operating handle 101, an operating tube 102, and a working module for mowing lawns. The operating handle 101 is provided at one end of the operating tube, and the working module and the battery pack are provided at the other end of the operating tube 102. When using the lawn mower, the user holds the operating handle 101 and controls the angle of the operating tube 102 to make the working module close to the lawn or vegetation. The working module generally includes a housing 600, a motor 100, an output shaft 110 connected to the motor 100, and a working head 200 matched with the output shaft 110 and provided at the bottom. The working head 200 includes a cutter disc and a detachable blade 210 provided on the cutter disc. The rotary motion of the cutter disc and the blade 210 is driven by the motor 100 to achieve lawn mowing. Or the working head 200 includes a mowing head and a nylon rope thereof. The mowing head is driven by the motor 100, and the nylon rope is swung to achieve lawn mowing. There is no limitation on the way the working head 200 mows the lawn.

[0030] Among them, a spacer 300 is usually provided between the motor 100 and the working head 200 in the mower 1. The spacer 300 is used to separate the housing and the working head to prevent the housing and the working head, which have large differences in movement speed, from affecting each other. The spacer 300 can be a partition 302 that plays a spacing role, or a fan 301 for spacing and heat dissipation. There is a gap between the motor 100 and the spacer 300. When the working head 200 cuts at high speed, grass clippings and sand and gravel splash and enter the gap between the motor 100 and the spacer 300. If they continue to accumulate, the resistance of the fan 301 will be increased, and even pushed to the output shaft 110, hindering the rotation of the output shaft 110, thereby affecting the rotation of the spacer 300 or the working head 200. In the prior art, a shielding structure for protecting the gap is provided on the outer wall of the spacer 300, which can reduce the entry of foreign debris at the outermost layer, but some debris from the working head 200 will still enter the spacer 300 near the output shaft 110, affecting the use.

[0031] Based on this, the present application provides a grass trimmer 1 to solve the above technical problems, as detailed in the following embodiments.

[0032] See also Figures 2 to 5 As shown, a grass trimmer 1 provided in one embodiment of the present application includes a shell 600, a working head 200 and a spacer 300, wherein a motor 100 is arranged in the shell 600; the working head 200 rotates under the drive of the motor 100; the spacer 300 is located between the shell 600 and the working head 200; and there is an assembly gap between the spacer 300 and the shell 600 along the direction of the output shaft 110 of the motor 100, the grass trimmer 1 includes a first blocking structure, which is arranged around the output shaft 110 of the motor 100 and is used to shield or mask the assembly gap; the grass trimmer 1 includes a second blocking structure, which is arranged around the first blocking structure and is used to shield or mask the assembly gap.

[0033] The second blocking structure surrounds the first blocking structure, and the second blocking structure is used to block debris in the external environment from entering the assembly gap, and the first blocking structure is used to block a small amount of debris passing through the second blocking structure or debris vertically entering the spacer from the working head portion. The first blocking structure and the second blocking structure form a two-stage blocking structure, which improves the blocking effect, effectively prevents the entry of debris, and increases the service life of the mower 1.

[0034] Specifically, the motor 100 is arranged inside the housing 600, the spacer 300 is arranged outside the housing 600, the output shaft 110 of the motor 100 extends from the housing 600 to connect the working head 200, the output shaft 110 of the motor 100 drives the working head 200 and the spacer 300 at the same time, and the spacer 300 is arranged between the housing 600 and the working head 200. There is an assembly gap between the spacer 300 and the housing 600 along the direction of the output shaft 110 of the motor 100, and the first blocking structure and the second blocking structure shield or mask the assembly gap at different positions to improve the blocking effect.

[0035] In a specific embodiment, the assembly gap is divided into two types, namely, a first assembly gap 400 and a second assembly gap 500, wherein the first assembly gap 400 is the gap between the internal shell 600 and the spacer 300, and the second assembly gap 500 is the gap between the outer edge of the spacer 300 and the shell edge. The second assembly gap 500 surrounds the first assembly gap 400, and debris such as grass clippings or sand and gravel from the outside will enter the interior from the second assembly gap 500. The second blocking structure shields or masks the second assembly gap 500, forming a gap direction similar to a "maze", and debris cannot directly enter the second assembly gap 500, which can effectively prevent debris from entering; if a small amount of debris bypasses the second blocking structure and enters the second assembly gap 500, this part of the debris moves inside the spacer 300 and continues to enter the first gap. Or part of the debris rolled up inside the working head 200 will enter axially to a position close to the first assembly gap, and further enter to a position closer to the transmission shaft through the first assembly gap 400, and then the first blocking structure will be used to shield the first assembly gap 400 to form a structure similar to a second-level "maze", blocking the entry of debris for the second time, and further reducing the probability of debris entering.

[0036] In one embodiment of the present application, Figure 3 and Figure 4 As shown, the first blocking structure includes an inner ring portion 310 and a first protrusion 610, wherein the inner ring portion 310 is located on the spacer 300 and is arranged around the output shaft 110 of the motor 100; the first protrusion 610 protrudes from the housing 600, and the first protrusion 610 covers the inner ring portion 310, and the inner ring portion 310 and the first protrusion 610 at least partially cover the opposite surfaces. The inner ring portion 310 and the first protrusion 610 cooperate with each other to play a blocking role.

[0037] Specifically, the inner ring portion 310 and the first protrusion 610 are combined to form a first blocking structure, wherein the inner ring portion 310 surrounds the output shaft 110 of the motor 100, and the inner ring portion 310 is opposite to the housing 600 in the axial direction, and a first assembly gap 400 is formed between the inner ring portion 310 and the housing 600, and the first assembly gap 400 connects the internal space of the spacer 300 and the input shaft space, and debris can horizontally enter the first assembly gap 400 and then reach the input shaft. It should be noted that the horizontal movement of debris is based on the plane where the fan 301 is located radially as a horizontal reference. The first protrusion 610 protrudes along the axial direction of the spacer 300, cutting off the horizontal moving path of debris, so that the debris cannot enter the first assembly gap 400 horizontally. The first blocking structure is a "maze" structure. The horizontally moving debris needs to change to move in one axial direction and then turn to move in the other axial direction before entering the gap. It is difficult for the debris to complete the complex path conversion under the action of inertia, which greatly reduces the probability of debris entering the gap and can effectively block the debris.

[0038] In a specific embodiment, the inner ring portion 310 is an annular structure protruding from the spacer 300 body. The inner ring portion 310 has an inner ring surface facing the output shaft 110 and an outer ring surface facing the outside of the annular structure. Similarly, the first protrusion 610 surrounds the output shaft 110 and has a protruding inner surface and a protruding outer surface. In one embodiment, the protruding outer surface and the inner ring surface cooperate with each other to form a first blocking structure. In another embodiment, the protruding inner surface and the outer ring surface cooperate with each other to form a first blocking structure.

[0039] In one embodiment of the present application, Figure 3 and Figure 4 As shown, the grass trimmer 1 further includes a bearing 700 , which is sleeved on the output shaft 110 ; the first protrusion 610 is arranged around the bearing 700 .

[0040] Specifically, the output shaft 110 of the motor 100 extends out of the housing 600. When the output shaft 110 rotates, the housing 600 is fixed, so the bearing 700 is used to support the relative rotation between the output shaft 110 and the housing 600 to reduce the friction coefficient. The first protrusion 610 on the housing 600 surrounds the bearing 700, and the first protrusion 610 can also serve as a positioning flange of the bearing 700. The bearing 700 is installed on the housing 600 through the positioning flange of the bearing 700. The first blocking structure can effectively prevent debris from entering the bearing 700.

[0041] In one embodiment of the present application, Figure 3 and Figure 4As shown, the second blocking structure includes an outer edge portion 320 and a second protrusion portion 620, wherein the outer edge portion 320 is located on the spacer 300 and is arranged around the first blocking structure; the second protrusion portion 620 protrudes from the housing 600, and the second protrusion portion 620 covers the outer edge portion 320, and the outer edge portion 320 and the second protrusion portion 620 at least partially cover the opposite surfaces. The outer edge portion 320 and the second protrusion portion 620 cooperate to prevent foreign matter from entering the interior of the spacer 300 and the housing 600 from the outer edge portion 320.

[0042] Specifically, the outer edge 320 and the second protrusion 620 are combined to form a second blocking structure, wherein the outer edge 320 includes the outermost annular surface of the spacer 300, the outer edge 320 is coaxial with the inner ring 310, the outer edge 320 surrounds the inner ring 310 and the output shaft 110 of the motor 100, the outer edge 320 is opposite to the housing 600 in the axial direction, and the outer edge 320 and the housing 600 are between the second assembly gap 500, the second assembly gap 500 connects the external space of the grass trimmer 1 and the internal space of the fan 301, and debris can horizontally enter the second assembly gap 500 and then reach the inside of the fan 301. It should be noted that the horizontal movement of debris is based on the plane where the fan 301 is located radially as the horizontal reference. The second protrusion 620 protrudes along the axial direction of the fan 301, cutting off the horizontal moving path of debris, so that the debris cannot enter the second assembly gap 500 horizontally. The second blocking structure is a "maze" structure. The horizontally moving debris needs to change to move in one axial direction and then turn to move in the other axial direction before entering the second blocking mechanism. It is difficult for the debris to complete the complex path conversion under the action of inertia, which greatly reduces the probability of debris entering the gap and can effectively block the debris.

[0043] In a specific embodiment, Figure 5 As shown, the spacer 300 is a partition 302, and the outer edge of the partition 302 is an annular structure protruding from the partition body. The outer edge has an inner edge surface facing the output shaft 110 and an outer edge surface facing the outside of the annular structure. Similarly, the first protrusion 610 surrounds the output shaft and has a protruding inner edge surface facing the output shaft and a protruding outer edge surface facing the outside. In one embodiment, the protruding outer edge surface and the inner edge surface cooperate with each other to form a second blocking structure. In another embodiment, the protruding inner edge surface and the outer edge surface cooperate with each other to form a second blocking structure.

[0044] In one embodiment of the present application, Figure 3 , Figure 7 and Figure 8As shown, the spacer 300 is a fan 301, and the fan 301 includes blades 330 and connecting ribs 340. The connecting ribs 340 are arranged around the output shaft 110 of the motor 100, and one end of a plurality of blades 330 is arranged around the connecting rib 340; the axial height of the blade 330 is less than the axial height of the connecting rib 340, so that there is a gap between the blade 330 and the working head 200, thereby avoiding the adhesion of the blade 330 to the working head 200 and facilitating the disassembly of the fan 301.

[0045] Specifically, the connecting rib 340 surrounds the axis of the fan 301 and is used to connect the blades 330. One end of the plurality of blades 330 facing the axis is connected to the connecting rib 340. The output shaft 110 drives the blades 330 to rotate by driving the connecting rib 340. The motor 100 is located inside the housing 600. The output shaft 110 of the motor 100 extends out of the housing 600. A bearing 700 is provided at the position where the output shaft 110 contacts the housing 600. The bearing 700 is used to support the relative rotation between the output shaft 110 and the housing 600. The portion of the output shaft 110 extending out of the housing 600 is sequentially sleeved with the fan 301 and the working head 200, and the fan 301 and the working head 200 are driven to rotate simultaneously when rotating. The connecting rib 340 in the fan 301 abuts against the working head 200. The axial height of the blade 330 is less than the connecting rib 340. Therefore, there is a gap between the blade 330 and the working head 200. If the blade 330 is in full contact with the working head 200, after long-term use, the contact surface between the working head 200 and the blade 330 will be adhered. Therefore, the gap between the blade 330 and the working head 200 can reduce the contact area between the fan 301 and the working head 200, making it easier to disassemble the fan 301. In one embodiment of the present application, the axial height of the blade 330 is a, and the axial height of the connecting rib 340 is b; wherein 0.1mm≤ba≤0.3mm. The height difference between the axial height of the blade 330 and the axial height of the connecting rib 340 is between 0.1mm-0.3mm, which can better avoid the adhesion of the blade 330 and the working head 200 and ensure the structural stability of the fan 301.

[0046] In a specific embodiment, the axial height of the blade 330 is smaller than the axial height of the connecting rib 340 by 0.1 mm, 0.2 mm or 0.3 mm.

[0047] In one embodiment of the present application, the fan 301 includes a positioning hole 350, and the positioning hole 350 is used to accommodate a positioning pin, and the positioning hole 350 is configured so that after the positioning pin passes through the positioning hole 350, an angle greater than 0 degrees is formed between the axis of the positioning pin and the axis of the fan 301. When the work head 200 is disassembled, the positioning pin is simultaneously inserted into the positioning hole 350 and a relatively fixed structure to fix the fan 301. The positioning pin is inserted into the positioning hole 350 at an angle greater than 0 degrees, which better matches the position of the closed circular hole structure of the positioning hole 350. The closed circular hole structure of the positioning hole 350 has a higher strength and reduces safety hazards.

[0048] Specifically, when the working head 200 of the grass trimmer 1 is disassembled, the fan 301 needs to be fixed so that the fan 301 does not rotate with the working head 200, so a positioning hole 350 is provided on the fan 301. When the working head 200 needs to be disassembled, the positioning pin is passed through the positioning hole 350, and one end of the positioning pin is inserted into the fixed structure to fix the fan 301. In the existing fan 301, a protruding circular hole structure is provided at the edge as a positioning hole, but the circular hole structure is open at the position of the original edge of the fan 301 that is not protruding, and cannot be closed, or the circular hole structure is recessed inward at the edge of the fan 301 to form a circular hole structure as a positioning hole, and the indented circular hole structure is open at the position of the original edge of the fan 301 when it is not indented, and cannot form a completely closed circular hole structure. The strength of the positioning hole 350 that cannot be completely closed is not high. When subjected to a certain rotational stress, there is a risk of edge damage, and the damaged part may be thrown out after breaking into pieces, causing safety hazards. Therefore, the positioning hole 350 is set as a closed circular hole structure to avoid the risk of damage. In addition, the positioning hole is set to an obliquely extending structure, so that after the positioning pin passes through the positioning hole 350, the angle between the axis of the positioning pin and the axis of the fan 301 is greater than 0 degrees, that is, the positioning pin is fixed by oblique insertion, and the positioning hole 350 avoids the edge position of the fan, thereby forming a closed structure, increasing strength, and reducing safety hazards.

[0049] In other embodiments, the positioning hole 350 is provided on the fan 301, and the fixing hole is provided on a fixed structure that does not rotate relative to the rotatable fan 301, such as the housing 600 of the motor 100 or the partition 302. The line connecting the axis of the positioning hole 350 and the axis of the fixing hole is not parallel to the axis of the fan 301, and after the positioning pin passes through the positioning hole 350 and is fixed to the fixing hole, the axis of the positioning pin is oblique.

[0050] In one embodiment of the present application, the positioning hole 350 includes a convex rib, and the convex rib surrounds the opening of the positioning hole 350. The convex rib is used to further increase the strength of the positioning hole 350.

[0051] Specifically, the convex rib protrudes from the surface of the fan 301 , increasing the contact area between the positioning hole 350 and the positioning pin, and can increase the strength of the positioning hole 350 .

[0052] In one embodiment of the present application, Figure 6 As shown, the housing 600 is provided with a heat dissipation port 630, which is located on the side of the housing 600 facing the fan 301; the fan 301 includes a plurality of blades 330, and a heat dissipation duct 360 is formed between adjacent blades 330; at least part of the heat dissipation port 630 and the heat dissipation duct 360 are located on the same ventilation path. The heat dissipation port 630 and the heat dissipation duct 360 can effectively prevent the fan 301 from blocking the heat dissipation, thereby ensuring the heat dissipation effect of the heat dissipation port 630.

[0053] Specifically, the heat generated by the motor 100 is discharged through the heat dissipation port 630, and the efficiency of heat dissipation is accelerated under the rotation of the fan 301. The heat dissipation port 630 is opposite to the gap between adjacent blades 330. After the heat is discharged from the heat dissipation port 630, it passes through the heat dissipation duct 360 formed by the gap between adjacent blades 330 to achieve effective heat dissipation.

[0054] In one embodiment of the present application, the heat dissipation openings 630 are evenly distributed around the axis of the motor 100. The evenly arranged heat dissipation openings 630 allow heat to be evenly discharged in the housing 600, thereby ensuring the stability of heat dissipation.

[0055] Specifically, during the heat dissipation process, the fan 301 rotates at high speed on the ventilation path of the heat dissipation port 630 to form an airflow. The heat dissipation port 630 is evenly distributed around the axis of the motor 100 to ensure that the airflow rate of each circumferential part of the fan 301 is the same, ensuring that the heat is evenly discharged in the shell 600 with high stability.

[0056] In another embodiment, the heat dissipation openings 630 are evenly distributed along the radial direction of the housing 600, so that the heat dissipation openings 630 evenly discharge heat in the radial direction of the housing 600. In other embodiments, the heat dissipation openings 630 are unevenly distributed on the housing 600, which also falls within the protection scope of this application.

[0057] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0058] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A lawn mower, characterized in that: include: A housing, wherein a motor is arranged in the housing; A working head is driven to rotate by the motor; a spacer, used for spacing the housing and the working head and located between the housing and the working head; and An assembly gap is provided between the spacer and the housing along the direction of the output shaft of the motor, and the grass trimmer comprises a first blocking structure, which is arranged around the output shaft of the motor and is used to shield or conceal the assembly gap; The lawn mower further comprises a second blocking structure, which is arranged around the first blocking structure and is used to shield or conceal the assembly gap.

2. The grass trimmer according to claim 1, characterized in that: The first blocking structure comprises: an inner ring portion, the inner ring portion being located on the spacer and arranged around the output shaft of the motor; A first protrusion protrudes from the shell and covers the inner ring portion, and the inner ring portion and the first protrusion at least partially cover the surfaces facing each other.

3. The grass trimmer according to claim 2, characterized in that: The grass trimmer further comprises: a bearing, wherein the bearing sleeve is arranged on the output shaft; The first protrusion is arranged around the bearing.

4. The grass trimmer according to claim 1, characterized in that: The second blocking structure comprises: an outer edge portion, the outer edge portion is located on the spacer and is disposed around the first blocking structure; A second protrusion protrudes from the shell, and the second protrusion covers the outer edge, and the outer edge and the second protrusion at least partially cover the surfaces facing each other.

5. The grass trimmer according to claim 1, characterized in that: The spacer is a fan, and the fan includes: blade; A connecting rib, the connecting rib is arranged around the output shaft of the motor, and one end of the plurality of blades is arranged around the connecting rib; The axial height of the blade is smaller than the axial height of the connecting rib, so that there is a gap between the blade and the working head.

6. The grass trimmer according to claim 5, characterized in that: The axial height of the blade is a, and the axial height of the connecting rib is b; wherein 0.1 mm ≤ ba ≤ 0.3 mm.

7. The grass trimmer according to claim 5, characterized in that: The fan comprises: A positioning hole is used to accommodate a positioning pin, and the positioning hole is configured so that after the positioning pin passes through the positioning hole, an angle greater than 0 degrees is formed between the axis of the positioning pin and the axis of the fan.

8. The grass trimmer according to claim 7, characterized in that: The positioning hole comprises: A convex rib surrounds the opening of the positioning hole.

9. The grass trimmer according to claim 1, characterized in that: The spacer is a fan, and the housing is provided with: A heat dissipation port, the heat dissipation port being located on a side of the housing facing the fan; The fan comprises a plurality of blades, and a heat dissipation duct is formed between adjacent blades; At least part of the heat dissipation openings and the heat dissipation air ducts are located on the same ventilation path.

10. The grass trimmer according to claim 9, characterized in that: The heat dissipation openings are evenly distributed around the axis of the motor.

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