Cutter head, grass shredding structure and lawn mower

Abstract

A cutter head, a grass shredding structure, and a lawn mower. The cutter head comprises: a plate body (4) and blades (6); the plate body (4) comprises a plate body A surface, a plate body B surface opposite to the plate body A surface, and a plate body edge part (42); a central part (43) connected to a rotary driving member (7) is provided on the plate body A surface; the plate body edge part (42) can be connected to mowing cutters (1); the blades (6) are arranged on the plate body A surface and are fixedly connected to the plate body A surface; the grass shredding structure comprises the cutter head and a protective shield sleeved on the plate body A surface and the plate body edge part (42); the protective shield is provided with a plurality of air guide holes in the circumferential direction of the cutter head; the lawn mower has the cutter head or the grass shredding structure.

Description

A blade disc, a grass-shredding structure, and a lawnmower Technical Field

[0001] This invention relates to the field of lawnmower accessories technology, specifically to a blade disc, a grass-shredding structure, and a lawnmower. Background Technology

[0002] With the increasing popularity of urban greening and home gardening, lawnmowers have become an indispensable tool for maintaining lawns and vegetation;

[0003] Existing lawnmowers, especially lawnmower robots, consist of a cutting disc and blades connected around it; a motor drives the cutting disc to rotate, which in turn drives the blades to rotate and complete the cutting.

[0004] During the mowing process, the grass is chopped and the juice inside flows out, or the grass clippings get wet. This causes the grass clippings to stick together with the juice or water and form clumps. These clumps are discharged from the mowing robot. These clumps not only affect the appearance of the lawn, but also accumulate on the lawn, affecting the lawn's breathability and drainage. They also increase the workload of cleaning up the clumps and affect the user experience of the mowing robot.

[0005] Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention provides a blade disc, a grass-shredding structure, and a lawnmower that can reduce grass clump formation.

[0007] The first technical solution adopted by the present invention to solve its technical problem is:

[0008] A cutter head includes: a disc body and fan blades;

[0009] The disk body includes a disk body A surface, a disk body B surface opposite to the disk body A surface, and a disk body edge portion;

[0010] The disk body A surface is provided with a central part that is connected to the rotary drive component;

[0011] A grass-cutting knife can be connected to the edge of the disc body;

[0012] The fan blades are disposed on the surface A of the disk body and are fixedly connected to the surface A of the disk body.

[0013] As described above, the blades of the cutter disc are a plurality of blades arranged radially from the center of the disc body to the edge of the disc body.

[0014] As described above, the blades of the cutter head are equidistantly distributed on the disc body.

[0015] As described above, the blades of the cutter head are arranged in an arc shape.

[0016] As described above, the blades of the cutter disc include a blade E end near the center and a blade F end near the edge of the disc body; the height of the blades increases from the blade E end to the blade F end.

[0017] As described above, the blades of the cutter disc include a blade C surface and a blade D surface, and the slope of the blade C surface relative to the disc surface increases from the blade E end to the blade F end.

[0018] As described above, in the cutter head, the deflection of the fan blades increases from the E end to the F end of the fan blades.

[0019] As described above, in the cutter head, the F end of the fan blade and the edge of the disc body are located on the same vertical axis.

[0020] As described above, the blade also includes a blade tip located between the blade C surface and the blade D surface;

[0021] The F end of the fan blade includes a windward section, one end of which is connected to the edge of the disc body, and the other end of which is connected to the top of the fan blade.

[0022] As described above, the air-facing portion of the cutter head is tangent to the periphery of the disc body.

[0023] As described above, in the blade disc, the distance between the C-surface of the blade and the D-surface of the blade increases from the tip of the blade to the A-surface of the disc body.

[0024] As described above, the A-side of the cutter head is inclined from the center to the edge of the cutter head.

[0025] As described above, the grass-cutting blade is connected to the blade disc via a snap-fit ​​mechanism.

[0026] As described above, the blade includes a blade, a connecting seat, and a latch;

[0027] The blade is rotatably connected to the connecting seat;

[0028] The buckle is fixedly mounted on the connecting seat;

[0029] The disc body is provided with a slot that matches the buckle.

[0030] The second technical solution adopted by the present invention to solve its technical problem is:

[0031] A grass-shredding structure includes a blade disc as described above and a protective cover fitted on the A-side of the disc body and the edge of the disc body;

[0032] The protective cover has several air guide holes along the circumference of the cutter head.

[0033] The third technical solution adopted by the present invention to solve its technical problem is:

[0034] A lawnmower having the aforementioned blade or the aforementioned grass-shredding structure.

[0035] The beneficial effects of this invention are:

[0036] By setting fan blades on surface A, the fan blades rotate together with the blade disc as it rotates, thereby generating airflow to shred the grass and reduce the formation of grass clumps. Attached Figure Description

[0037] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0038] Figure 1 is a schematic diagram of the connection relationship between the blade disc, the grass cutter, and the rotary drive component in this invention.

[0039] Figure 2 is a top view of the blade disc and the grass-cutting blade in this invention;

[0040] Figure 3 is a three-dimensional structural diagram of the blade disc and the lawn mower in this invention;

[0041] Figure 4 is a perspective view of the lawn mower in this invention;

[0042] Figure 5 is an exploded view of the lawn mower in this invention;

[0043] Figure 6 is a schematic diagram of the structure of the blade disc with the first and second locking grooves before it is connected to the lawn mower in this invention;

[0044] Figure 7 is a schematic diagram of the structure of the blade disc with the first and second locking grooves connected to the lawn mower in this invention.

[0045] Figure 8 is a schematic diagram of the structure of the blade disc before it is connected to the lawn mower, with the third slot provided on one side.

[0046] Figure 9 is a schematic diagram of the structure of the blade disc after the third slot is connected to the grass cutter in this invention;

[0047] The markings in the attached diagram are as follows:

[0048] 1-Grass mower; 10-Blade; 11-First blade; 12-Second blade; 13-Connecting hole; 21-Snap fastener; 211-First snap fastener; 2111-First lug; 212-Second snap fastener; 2121-Second lug; 3-Connecting seat; 31-Mounting hole; 32-Clamping component; 4-Blade disc; 41-Slot; 411-First snap fastener slot; 412-Second snap fastener slot; 413-Third slot; 414-First beveled guide slot; 415-Second beveled guide slot; 42-Edge of disc body; 43-Center; 5-Screw; 501-Threaded rod; 502-Screw head; 51-First screw; 52-Second screw; 6-Fan blade; 61-Fan blade tip; 62-Wind-facing part; 7-Rotation drive component. Detailed Implementation

[0049] The following will clearly and completely describe the concept, specific structure, and technical effects of the present invention in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. Furthermore, all connections / linkages involved in the patent do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this invention can be combined interactively without contradicting each other.

[0050] Referring to Figures 1 to 3, a cutter head includes: a disc body 4 and fan blades 6;

[0051] The disk body 4 includes a disk body A surface, a disk body B surface opposite to the disk body A surface, and a disk body edge portion 42;

[0052] The disk body A surface is provided with a central part 43 that is connected to the rotary drive component 7;

[0053] The edge portion 42 of the disc body can be connected to a grass-cutting knife 1;

[0054] The fan blade 6 is disposed on the surface of the disc body A and is fixedly connected to the surface of the disc body A. The output end of the rotary drive 7 is connected to the central part 43. When the rotary drive 7 is activated, it drives the cutter head to rotate. As the fan blade 6 rotates, the air molecules on the surface of the disc body A are pushed by the fan blade 6, the air velocity increases and the pressure decreases, and a pressure difference is generated on the surface of the disc body A with the surrounding environment. The pressure difference causes air to flow from the high pressure area (the periphery of the disc body) to the low pressure area (the surface of the disc body A).

[0055] During mowing, the rotating blade 1 generates centrifugal force, which causes the lightweight grass clippings to be thrown upwards along the tangent of the rotating blade disc at the moment they are cut. Some of the clippings are thrown to the high-pressure zone, and some to the low-pressure zone. Some of the clippings in the high-pressure zone move to the low-pressure zone under the influence of the pressure difference. At this time, there are more clippings on the surface of the disc A. Under the action of the fan blade 6, the air flow speed on the surface of the disc A is fast. The high-speed air flow is used to agitate the clippings and prevent them from clumping together, thereby reducing the formation of grass clumps. Subsequently, some clippings are thrown out of the blade disc by the centrifugal force of the disc 4 and the fan blade 6, as well as by gravity. This allows mowing, grass removal, and grass shredding to be completed simultaneously, thereby reducing the formation of grass clumps. Furthermore, when the clippings processed by the blade disc fall back onto the lawn, they are in a loose state, so they do not affect the lawn's aeration and drainage.

[0056] Therefore, it can be seen that when the cutter head in this embodiment is in use, the B side of the disc body faces the lawn, while the A side of the cutter head and the rotating drive component 7 face away from the lawn.

[0057] Specifically, the rotary drive 7 is a device, such as a motor, that transmits the rotational motion of the power source to the cutter head.

[0058] Furthermore, there are several fan blades 6, arranged radially from the center 43 of the disc body to the edge 42. The fan blades 6 can extend radially along the disc body 4 or be arranged off-radial from the disc body 4. Having several fan blades 6 helps to distribute airflow evenly, increase wind speed, and reduce the rotational energy consumption of the rotating drive component 7. When the cutter disc rotates, it can push air more evenly from the center 43 to the edge 42 of the disc body, reducing airflow unevenness, reducing the formation of turbulence and eddies, thereby avoiding excessively strong or weak airflow in local areas, which would affect the grass removal effect.

[0059] Among them, the shape of the fan blade 6 can be a planar fan blade, a spiral fan blade, an airfoil fan blade, etc.;

[0060] The number of fan blades 6 can be 1-2. This arrangement makes the blade disc lighter and reduces the inertia when rotating. However, the correspondingly lower airflow will result in poor grass shredding and removal. The number of fan blades 6 can also be 3-10 or even more. The number can be selected according to the size of the blade disc area, as long as the number of fan blades 6 can maintain an airflow to shred and remove grass when the blade disc rotates. The blade disc in this figure is for a household lawnmower robot. Due to the size limitation of the lawnmower robot, the number of fan blades 6 in the figure of this embodiment is three.

[0061] Preferably, the number of fan blades 6 is odd. If the number of fan blades 6 is even, it means that there is a fan blade opposite each fan blade. Since the structure of each fan blade is the same, when one fan blade rotates and vibrates, the probability of the fan blade opposite it vibrating will be greater, thus amplifying the impact of vibration on the rotation of the cutter head, affecting the smooth operation of the cutter head, and thus affecting the mowing effect. The fact that the number of fan blades 6 is odd can avoid this problem.

[0062] Specifically, each of the fan blades 6 is equidistantly distributed on the disc body 4 to ensure the uniformity and continuity of airflow; and it helps to maintain the weight balance of the blade disc, avoiding vibration of the blade disc due to uneven weight distribution, which would affect the mowing effect.

[0063] Specifically, the fan blade 6 is arranged in an arc shape. Compared with a straight fan blade, the arc-shaped fan blade has a larger surface area, which means a larger area in contact with the air. When the blade rotates, the airflow direction is stronger and more complex, resulting in better grass shredding effect.

[0064] More specifically, the fan blade 6 includes a fan blade E end near the center 43 and a fan blade F end near the edge of the disc body 4; the height of the fan blade 6 increases from the fan blade E end to the fan blade F end. The height of the fan blade F end is greater than the height of the fan blade E end, so the fan blade F end can push a larger amount of air, thereby generating a larger air volume. That is to say, the pressure at the fan blade F end is lower than the pressure at the fan blade E end. When grass clippings fall above the fan blade E end, the grass clippings move towards the fan blade F end under the action of the pressure difference; and since the distance from the fan blade F end to the center 43 is greater than the distance from the fan blade E end to the center 43, the centrifugal force generated by the fan blade F end will be greater, which can effectively throw out grass clippings.

[0065] More specifically, the fan blade 6 includes a fan blade C surface and a fan blade D surface. The slope of the fan blade C surface relative to the surface of the disk 4 with respect to the horizontal plane increases from the fan blade E end to the fan blade F end. This slope represents the included angle α of the fan blade C. The slope of the fan blade E end is low. When the cutter disk rotates, it pushes gas molecules out along the centrifugal force direction of the fan blade E end. Due to the large height of the fan blade F end, some of the ejected gas molecules flow to the adjacent fan blade F end and are then pushed by the fan blade F end to the top of the disk A surface, thereby forming an airflow from the fan blade E end to the fan blade F end. This airflow can drive the grass clippings to move, further reducing the air pressure at the fan blade F end and improving the grass clipping effect.

[0066] More specifically, the deflection of the fan blade 6 increases from the E end to the F end. This increased deflection further enhances the sweeping area at the F end of the fan blade and the airflow during rotation, thereby increasing the air delivery distance.

[0067] Specifically, the D-side of the fan blade is perpendicular to the A-side of the cutter head, and the slope and deflection of the aforementioned fan blade 6 are indicators used to measure the shape of the C-side of the fan blade.

[0068] More specifically, the end of the fan blade F and the edge of the disc body 42 are located on the same vertical axis. That is, the end of the fan blade F and the edge of the disc body 42 are arranged adjacent to each other. When the grass cutter 1 cuts grass clippings, the clippings are thrown upwards and more easily enter the low-pressure area.

[0069] More specifically, the fan blade 6 also includes a fan blade tip 61 located between the fan blade C surface and the fan blade D surface;

[0070] The F end of the fan blade includes a windward section 62, one end of which is connected to the edge of the disc 42, and the other end of which is connected to the tip of the fan blade 61. This connection means that the windward section 62 smoothly transitions between the edge of the disc 42 and the tip of the fan blade 61. The windward section 62 can reduce the air resistance to the cutter disc when it rotates. When the cutter disc rotates, the windward section 62 can guide the gas flow to the C-side, D-side, and tip of the fan blade 61, reducing the air resistance in the initial stage of the cutter disc's rotation and reducing the energy consumption of the rotary drive component 7.

[0071] More specifically, the windward portion 62 is tangent to the periphery of the disc body 4. When the fan blade 6 is arc-shaped, the air resistance during the rotation of the fan blade 6 can be further reduced.

[0072] More specifically, the distance between the C-side and D-side of the fan blade increases from the tip 61 of the fan blade towards the A-side of the disk body; that is, from a cross-sectional view, the C-side and D-side of the fan blade form an "A" shape. When the slope and deflection of the C-side of the fan blade relative to the surface of the disk body 4 increase from the E-side to the F-side, the air resistance experienced by the F-side of the fan blade during rotation is greater than that of the E-side, making it more susceptible to airflow interference and more prone to vibration. With long-term use, the F-side of the fan blade is more likely to deform or break, affecting the grass-chopping effect. Increasing the distance between the C-side and D-side of the fan blade can enhance the structural strength of the fan blade 6, reduce the vibration of the fan blade 6, improve the deformation resistance of the fan blade 6, and reduce the risk of breakage of the fan blade 6.

[0073] More specifically, the A-side of the disc is inclined from the center 43 to the edge 42. Under the influence of gravity, this helps guide air molecules from the center 43 to the edge 42, forming an airflow from the center 43 to the edge 42. This guides the grass clippings from the area of ​​low centrifugal force (center 43) to the area of ​​high centrifugal force (edge ​​42), thus facilitating grass removal.

[0074] Currently, lawnmower blades on the market typically use fixed blades. As the lawnmower is used for a longer period of time, the blades wear down and the cutting effect becomes poor, requiring replacement. However, since the fixed blades are welded to the blade disc, replacing them requires disassembling the entire blade disc. Since the blade disc itself has a grass-chopping function, replacing it without damaging the grass-chopping structure would be too wasteful.

[0075] Referring to Figures 4 to 9, as an improvement, the lawn mower 1 is detachably connected to the disc body 4, such as by plugging, snap-fit, or screw connection, which is convenient and quick, and makes it easy for users to replace the lawn mower 1.

[0076] Taking the snap-fit ​​connection as an example, let me explain in detail how to achieve detachability:

[0077] Furthermore, the lawnmower 1 includes a blade 10, a connecting seat 3, and a buckle 21;

[0078] The blade 10 is rotatably connected to the connecting seat 3;

[0079] The buckle 21 is fixedly disposed on the connecting seat 3;

[0080] The disc body 4 is provided with a slot 41 that is adapted to the buckle 21.

[0081] When the disc 4 rotates, the blade 10 is thrown out to cut grass under the action of centrifugal force. When it is necessary to operate on the parts around the disc 4, in order to avoid touching the blade 10 and getting cut, the blade 10 can be rotated to a suitable position for operation.

[0082] Specifically, the latch 21 includes a first latch 211 located on the left side of the blade 10 and a second latch 212 located on the right side of the blade 11;

[0083] The first buckle 211 is provided with a first lug 2111, and the second buckle 212 is provided with a second lug 2121. The first lug 2111 and the second lug 2121 can be semi-circular protrusions or wedges.

[0084] The first buckle 211 and the second buckle 212 may be made of a material with elasticity, such as polyhexamethylene adipamide and modified ABS plastic;

[0085] The slot 41 includes a first latching slot 411 and a second latching slot 412. The openings of the first latching slot 411 and the second latching slot 412 are arranged in the circumferential direction of the disc body 4. The first latching slot 411 is adapted to the first lug 2111, and the second latching slot 412 is adapted to the second lug 2121.

[0086] This design allows users to operate with one hand. Referring to Figure 6, when the lawnmower needs to be installed, the thumb and forefinger can press against the first latch 211 and the second latch 212 respectively, applying force to squeeze the first latch 211 and the second latch 212 to deform them, pushing the first lug 2111 and the second lug 2121 into the first latch groove 411 and the second latch groove 412, and then release. Since the first latch 211 and the second latch 212 have a rebound force, when the hand is released, the first latch 211 and the second latch 212 spring back, thereby fixing the lawnmower on the disc body, as shown in Figure 7. When the lawnmower needs to be removed, the above operation process can be reversed.

[0087] The blade 10 is fixedly connected to the middle of the connecting seat 3. The first buckle 211 is connected to the left side of the connecting seat 3 and the second buckle 212 is connected to the right side of the connecting seat 3. The first buckle 211 and the second buckle 212 are located on both sides of the blade, which can provide better balance for the blade 10.

[0088] Since the blade 10 is the main consumable in the lawnmower structure, the blade 10 is detachably connected to the connecting seat 3. When the blade 10 wears out, it can be replaced without installing the connecting seat 3, further reducing material waste.

[0089] More specifically, it also includes screw 5, which has a threaded rod 501 and a screw head 502, the connecting seat 3 is provided with a mounting hole 31 in the middle, and the blade 11 is provided with a connecting hole 13;

[0090] The diameter of the connecting hole 13 is larger than the diameter of the threaded rod 501 and smaller than the diameter of the screw head 502;

[0091] The threaded rod 501 passes through the connecting hole 13 and the mounting hole 31, so that the movable position of the blade 11 is limited between the screw head 502 and the connecting seat 3.

[0092] Specifically, a nut 311 may be installed in the mounting hole 31, or the inner wall of the mounting hole 31 may be provided with an internal thread that matches the threaded rod 501;

[0093] The threaded rod 501 is screwed into the nut 311 or the mounting hole 31 and fixedly connected to the connecting seat 3.

[0094] More specifically, the blade 11 includes a first blade 11 disposed on the top of the connecting seat 3 and a second blade 112 disposed on the bottom of the connecting seat 3;

[0095] The screw 5 includes a first screw 51 located at the top of the connector 3 and a second screw 52 located at the bottom of the connector 3.

[0096] The dual-blade configuration helps to increase the amount of grass cut; since the first blade 11 is rotatably connected to the connecting seat 3 with the first screw 51 as the center and the second blade 112 is rotatably connected to the connecting seat 3 with the second screw 52 as the center; when the first blade 11 is cutting grass, the second blade 112 can also perform grass cutting operations at the same time.

[0097] Referring to Figures 8-9, more specifically, it also includes a clamping member 32, which is fixedly connected to the connecting seat 3, and the clamping member 32 is disposed between the first buckle 211 and the second buckle 212;

[0098] Furthermore, the slot 41 comprises a first latching slot 411, a second latching slot 412, a first inclined guide slot 414, and a second inclined guide slot 415, all with openings facing the circumference of the disc body 4.

[0099] The first latching groove 411 and the second latching groove 412 are both provided on one side of the disc body 4, and the other side of the disc body 4 is provided with a third latching groove 413;

[0100] The clamping member 32 can be adapted to the third slot 413. The clamping member 32 cooperates with the first buckle 211 and the second buckle 212 to fix the grass cutter along the height direction of the disc body 4, further improving the firmness of the connection seat 3 and the disc body 4.

[0101] The first snap-fit ​​groove 411 is adjacent to the first inclined guide groove 414; the first snap-fit ​​groove 411 and the first inclined guide groove 414 are arranged sequentially along the circumference of the disc body 4 from the center of the disc body 4.

[0102] The second snap-fit ​​groove 412 is adjacent to the second inclined guide groove 415; the second snap-fit ​​groove 412 and the second inclined guide groove 415 are arranged sequentially along the circumference of the disc body 4 from the center.

[0103] The second snap groove 412 and the second inclined guide groove 415 can guide the first snap 211 and the second snap 212 to deform and snap into the first snap groove 411 and the second snap groove 412.

[0104] A grass-shredding structure includes a blade disc as described above and a protective cover (not shown in the figure) fitted on the A-side of the disc body and the edge 42 of the disc body.

[0105] The protective cover has several air guide holes (not shown in the figure) along the circumference of the disc. When the disc is inside the protective cover, the grass clippings thrown upwards can collide with the inner wall of the protective cover and bounce back to surface A of the disc. With the protective cover in place, the air outlet of the fan blade 6 forms a circulating high-speed airflow between the inner wall of the protective cover and surface A of the disc, further agitating the grass clippings and reducing the probability of grass clumps forming.

[0106] A lawnmower having a blade disc as described above or a grass-chopping structure as described above, and thus having the aforementioned advantages.

[0107] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A cutter head, characterized in that, include: The disk body (4) and the fan blades (6); The disk body (4) includes a disk body A surface, a disk body B surface opposite to the disk body A surface, and a disk body edge portion (42); The disk body A surface is provided with a central part (43) that is connected to the rotary drive component (7); The edge (42) of the disc body can be connected to a grass cutter (1); The fan blade (6) is disposed on the surface of the disk body A and is fixedly connected to the surface of the disk body A.

2. The cutter head as described in claim 1, characterized in that: The fan blades (6) are a plurality of each fan blade (6) arranged radially from the center (43) of the disk body to the edge (42) of the disk body.

3. The cutter head as described in claim 2, characterized in that: Each of the fan blades (6) is equidistantly distributed on the disk body (4).

4. The cutter head as described in claim 1 or 2, characterized in that: The fan blades (6) are arranged in an arc shape.

5. The cutter head as described in claim 4, characterized in that: The fan blade (6) includes a fan blade E end near the center (43) and a fan blade F end near the edge of the disk body (4); the height of the fan blade (6) increases from the fan blade E end to the fan blade F end.

6. The cutter head as described in claim 5, characterized in that: The fan blade (6) includes a fan blade C surface and a fan blade D surface, and the slope of the fan blade C surface relative to the surface of the disk body (4) increases from the fan blade E end to the fan blade F end.

7. The cutter head as described in claim 5 or 6, characterized in that: The deflection of the fan blade (6) increases from the E end of the fan blade to the F end of the fan blade.

8. The cutter head as described in claim 5 or 6, characterized in that: The end of the fan blade F and the edge of the disk (42) are located on the same vertical axis.

9. The cutter head as described in claim 5, characterized in that: The fan blade (6) also includes a fan blade tip (61) located between the fan blade C surface and the fan blade D surface; The F end of the fan blade includes a windward portion (62), one end of which is connected to the edge portion (42) of the disc body, and the other end of which is connected to the top tip (61) of the fan blade.

10. The cutter head as described in claim 9, characterized in that: The windward portion (62) is tangent to the periphery of the disc body (4).

11. The cutter head as described in claim 9, characterized in that: The distance between the C-side of the fan blade and the D-side of the fan blade increases from the tip of the fan blade (61) to the A-side of the disk.

12. The cutter head as described in claim 9, characterized in that: The A-side of the disc is inclined from the center (43) to the edge (42).

13. The cutter head as described in claim 1, characterized in that: The grass cutter (1) is detachably connected to the blade disc (4).

14. The cutter head as described in claim 13, characterized in that: The grass cutter (1) and the blade disc (4) are connected by a snap-fit.

15. The cutter head as described in claim 14, characterized in that: The lawnmower (1) includes a blade (10), a connecting seat (3), and a buckle (21); The blade (10) is rotatably connected to the connecting seat (3); The buckle (21) is fixedly mounted on the connecting seat (3); The disc body (4) is provided with a slot (41) that is adapted to the buckle (21).

16. A grass-shredding structure, characterized in that: Includes the cutter head as described in any one of claims 1-15 and the protective cover sleeved on the A surface of the disc body and the edge portion (42) of the disc body; The protective cover has several air guide holes along the circumference of the cutter head.

17. A lawnmower, characterized in that: It has a blade disc as described in any one of claims 1-15 or a grass-chopping structure as described in claim 16.

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