Grass protection wheel of mowing robot, outer-layer flexible wheel sleeve and mowing robot

Abstract

The invention discloses a grass protecting wheel of a mowing robot, an outer-layer flexible wheel sleeve and the mowing robot, and the outer-layer flexible wheel sleeve is made of a flexible material and used for being arranged on the periphery of a tire of the mowing robot in a sleeving mode. The grass protection wheel comprises an inner-layer hard tire and an outer-layer flexible wheel sleeve, the inner-layer hard tire is connected with the hub or the driving shaft and provides structural support and torque output, the outer-layer flexible wheel sleeve is arranged on the periphery of the inner-layer hard tire in a sleeving mode and makes direct contact with a lawn, and structural support and torque transmission are guaranteed through the inner-layer hard tire. The outer-layer flexible wheel sleeve is made of a flexible material, has good buffering performance, can effectively absorb impact force, disperse pressure acting on the surface of a lawn and reduce impact and shear force on the lawn, so that lawn protection and terrain adaptability can be considered at the same time, lawn damage is reduced, and the service life of the lawn is prolonged. And the stability of the mowing robot walking on complex terrains is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mowing robots, and particularly relates to a grass-protecting wheel of a mowing robot, an outer flexible wheel cover and the mowing robot. BACKGROUND

[0002] In the actual operation process of the mowing robot, the interaction between the tire and the lawn has a decisive influence on the health status of the lawn and the operating performance of the machine. The conventional mowing robot generally adopts a single-layer hard rubber tire structure. When the machine starts, stops, differentially steers or performs a small-radius turning operation, significant shearing friction occurs between the tire surface and the lawn grass and soil. This friction not only causes the surface soil of the lawn to be excessively compacted, forming a persistent tire mark, which destroys the flatness and aesthetics of the lawn, and in severe cases, can also cause tearing damage to the local area of the lawn, affecting the normal development of the grass root system and the recovery ability of the lawn.

[0003] To alleviate such problems, some improvement schemes attempt to reduce the overall hardness of the tire, for example, by using soft rubber materials to reduce the direct impact on the lawn. However, such soft tires have a sharp decrease in adhesion to the ground in complex working conditions such as wet and slippery grass, inclined slopes or soft muddy ground, which easily causes tire skidding, significantly reduces the traction of the mowing robot, causes the mowing robot to have difficulty walking or the walking trajectory to deviate from the expected trajectory, and even risks loss of stability, thereby increasing the operation difficulty and potential safety hazards. The above contradictions show that the existing tire design cannot simultaneously meet the demands of lawn protection and terrain adaptability. SUMMARY

[0004] The purpose of the present application is to provide a grass-protecting wheel of a mowing robot, an outer flexible wheel cover and the mowing robot, which can simultaneously meet the demands of lawn protection and terrain adaptability, reduce lawn damage, and improve the stability of the mowing robot when walking on complex terrain.

[0005] In a first aspect of the present application, a grass-protecting wheel of a mowing robot is provided, which comprises an inner hard tire and an outer flexible wheel cover. The inner hard tire is connected with a hub or a drive shaft to provide structural support and torque output. The outer flexible wheel cover is made of a flexible material and is sleeved on the outer periphery of the inner hard tire to directly contact the lawn.

[0006] In some implementation schemes, a first interlocking structure is arranged on the outer periphery of the inner hard tire, and a second interlocking structure that cooperates with the first interlocking structure is arranged on the inner periphery of the outer flexible wheel cover. The first interlocking structure and the second interlocking structure are connected through friction and / or snap fit to inhibit relative sliding and achieve torque transmission.

[0007] In some embodiments, the outer flexible tire cover is detachably connected to the inner hard tire, and the outer flexible tire cover can be replaced independently.

[0008] In some embodiments, the inner hard tire has a first hardness, and the outer flexible tire cover has a second hardness, and the first hardness is greater than the second hardness.

[0009] In some embodiments, the outer flexible tire cover is a one-piece structure, and the outer flexible tire cover is sleeved on the outer periphery of the inner hard tire through elastic stretching.

[0010] In some embodiments, the outer flexible tire cover includes a belt-shaped tire cover body and assembly ports at both ends of the tire cover body, and the assembly ports at both ends of the tire cover body are connected through buckles, locks, drawstrings or fasteners, so that the tire cover body is tightly wrapped around the outer periphery of the inner hard tire.

[0011] In some embodiments, the outer flexible tire cover includes a plurality of structural layers, and each structural layer has a different hardness, and the outermost structural layer has the smallest hardness.

[0012] In some embodiments, the outer flexible tire cover is a split structure, and the outer flexible tire cover includes a plurality of tire cover modules, and each tire cover module is connected to the inner hard tire through a connecting member.

[0013] In a second aspect of the present application, an outer flexible tire cover is provided, which is used to be sleeved on the outer periphery of a tire of a mowing robot, and the outer flexible tire cover is made of a flexible material with a hardness lower than that of the tire, and an interlocking structure is arranged on the inner periphery of the outer flexible tire cover to frictionally and / or bucklingly cooperate with the outer periphery of the tire.

[0014] In a third aspect of the present application, a mowing robot is provided, which includes a walking mechanism, and the walking mechanism is provided with a grass protection wheel according to any one of the above.

[0015] Compared with the prior art, the outer flexible tire cover provided by the present application is made of a flexible material with a hardness lower than that of the tire, can be directly sleeved on the outer periphery of the tire of a mowing robot, can effectively absorb impact force, and can effectively disperse pressure acting on the surface of the lawn and reduce impact and shear force on the lawn.

[0016] The grass protection wheel provided by the application comprises an inner hard tire and an outer flexible tire cover, the inner hard tire has a certain structural strength, is connected with a hub or a driving shaft, and can ensure structural support and torque transmission; the outer flexible tire cover is made of flexible material, is sleeved on the outer periphery of the inner hard tire, directly contacts the lawn, and has a flexible structure, good buffering performance, can effectively absorb impact force, and disperses the pressure acting on the lawn surface, reduces the impact and shearing force on the lawn.

[0017] It can be seen that the application can simultaneously consider lawn protection and terrain adaptability by applying the outer flexible tire cover to the walking mechanism of the lawn mowing robot, and reduces lawn damage. Meanwhile, the outer flexible tire cover deforms under the self-weight pressure of the lawn mowing robot, can increase the contact area with the lawn, realizes a function similar to a track, and improves the stability of the lawn mowing robot on complex terrain. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic view of a grass protection wheel provided by the application installed on a hub.

[0019] Figure 2 is a structural schematic view of a grass protection wheel provided by the application.

[0020] Figure 3 is Figure 2 is an exploded structural schematic view of the grass protection wheel shown in

[0021] Figure 4 is a sectional view of a second grass protection wheel provided by the application.

[0022] Figure 5 is an exploded structural schematic view of a third grass protection wheel provided by the application.

[0023] Figure 6 is a structural schematic view of an inner hard tire in a fourth grass protection wheel provided by the application.

[0024] Figure 7 is Figure 6 is a sectional view of the grass protection wheel shown in

[0025] Figure 8 is a structural schematic view of an inner hard tire in a fifth grass protection wheel provided by the application.

[0026] Figure 9 is Figure 8 is a sectional view of the grass protection wheel shown in

[0027] Figure 10 is a structural schematic view of a sixth grass protection wheel provided by the application.

[0028] Figure 11This is a structural schematic diagram of the seventh type of weed protection wheel provided in this application.

[0029] Figure 12 This is a structural schematic diagram of the eighth type of weed protection wheel provided in this application.

[0030] Figure 13 This is a structural schematic diagram of the ninth type of weed protection wheel provided in this application.

[0031] Figure 14 yes Figure 13 The diagram shows the exploded structure of the weed protection wheel.

[0032] Figure 15 This is a schematic diagram of an outer flexible wheel sleeve provided in this application being fitted onto the outer periphery of the tire of a lawnmower robot.

[0033] Figure 16 This is a structural schematic diagram of a lawnmower robot provided in this application.

[0034] Explanation of markings in the diagram: 10. Weeding wheel; 1. Inner hard tire; 1' Tire; 11. First groove; 12. First protrusion; 13. Third groove; 14. Fourth groove; 15. Fourth protrusion; 16. First friction tread; 2. Outer flexible wheel sleeve; 21. Second groove; 22. Second protrusion; 23. Third protrusion; 24. Fifth groove; 25. Wheel sleeve body; 26. Hook; 27. Buckle; 28. Second friction tread; 2a. Wheel sleeve module; 2b. Connector; 20. Wheel hub; 100. Lawn mower robot. Detailed Implementation

[0035] To make the inventive objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] In the tire structure of traditional lawnmower robots, the use of a single layer of hard rubber material results in a large shear friction force between the tire and the lawn surface during start-up and stop operations, differential steering, or small-radius turns. This leads to the compaction of the lawn surface, the formation of wheel tracks, and localized tearing phenomena. Furthermore, if the tire hardness is reduced to lessen the force on the lawn, the effective adhesion between the tire and the ground is insufficient under conditions of wet grass, slopes, or soft ground, inducing slippage and weakening walking stability.

[0037] For example, when performing lawn mowing operations on wet and slippery sloping lawns, the lawn mowing robot makes small-radius turns. The single-layer hard tires, due to their high rigidity, cannot buffer the dynamic load during the turning process, causing the tire edges to exert concentrated shear stress on the lawn, tearing the surface of the lawn. At the same time, because the ground is slippery, although using softer tires can disperse some of the contact pressure, the excessive deformation will significantly reduce the grip, easily causing the tires to slip, making it difficult for the lawn mowing robot to walk or causing the walking trajectory to deviate from the expected path.

[0038] If the above-mentioned technical problems are not solved, the operational reliability of lawn mowing robots in complex terrain will continue to be affected, the degree of lawn damage will be further aggravated, the aesthetics and healthy growth of the lawn will be destroyed, and insufficient walking stability may also lead to the risk of equipment loss of control, resulting in reduced mowing efficiency and lawn maintenance quality.

[0039] In response, this application provides a lawn-protecting wheel 10 for a lawnmower robot, please refer to... Figures 1 to 3 The lawn mower 10 includes an inner hard tire 1 and an outer flexible wheel sleeve 2. The inner hard tire 1 is connected to the wheel hub 20 to provide structural support and torque output. In some other embodiments, the hard tire may also be connected to the drive shaft. The outer flexible wheel sleeve 2 is made of flexible material and is fitted around the outer periphery of the inner hard tire 1, making direct contact with the lawn.

[0040] Among them, the lawn protection wheel 10 refers to a wheel specifically designed for lawn mowing robots to protect the lawn from damage during operation while providing the necessary traction. Its core function is to balance the physical impact of the lawn mowing robot on the lawn when it moves on the lawn with the movement requirements of the lawn mowing robot itself.

[0041] The inner hard tire 1 refers to the structural layer inside the weed guard wheel 10, which is mainly composed of an elastic material with a certain degree of hardness. This inner hard tire 1 is used to bear the weight of the machine, provide stable structural support, and effectively transmit torque from the drive system to the outside of the weed guard wheel. The structural support provided by the inner hard tire 1 refers to the ability of the weed guard wheel 10 to resist deformation when bearing the weight and operating load of the mowing robot.

[0042] The outer flexible wheel sleeve 2 refers to the flexible layer fitted around the outer periphery of the inner hard tire 1. This outer flexible wheel sleeve 2 is mainly composed of flexible materials, and its main function is to be in direct contact with the lawn, absorbing impact and dispersing pressure through its flexible properties to reduce the shearing and compaction effects on the lawn.

[0043] Therefore, the lawn-protecting wheel 10 of this application, through the inner hard tire 1 providing stable support and power transmission, and the outer flexible wheel sleeve 2 providing flexible contact and lawn protection, successfully solves the inherent conflict between protecting the lawn and providing traction in traditional lawn-mowing robot tires. This layered design allows the lawn-protecting wheel to simultaneously meet the dual requirements of high traction and low lawn damage, balancing lawn protection and terrain adaptability, and reducing lawn damage. Simultaneously, the outer flexible wheel sleeve 2 deforms under the weight of the lawn-mowing robot, increasing the contact area with the lawn and providing sufficient friction to cope with slippery surfaces, achieving a track-like function and improving the stability of the lawn-mowing robot in complex terrain. This functional optimization and balance provides an innovative solution for the efficient and environmentally friendly operation of lawn-mowing robots in different working environments.

[0044] This application does not limit the specific connection method between the inner hard tire 1 and the outer flexible wheel sleeve 2. For example, the inner hard tire 1 and the outer flexible wheel sleeve 2 can be fixedly connected, such as by adhesive bonding or ultrasonic welding. Alternatively, they can be detachably connected. In one detachable connection method, the inner hard tire 1 can be a conventional tire from an existing lawnmower robot, with friction treads on its outer circumference. The outer flexible wheel sleeve 2 temporarily increases its inner diameter through elastic extension and fits around the outer circumference of the inner hard tire 1. In another detachable connection method, the outer flexible wheel sleeve 2 can be fixed to the outer circumference of the inner hard tire 1 using magnetic components or Velcro. It is understood that when the two are detachably connected, the outer flexible wheel sleeve 2 can be replaced independently. Therefore, when the outer flexible wheel sleeve 2, which is in direct contact with the lawn, wears down due to long-term use, it is not necessary to replace the entire lawnmower as in traditional solutions; instead, only the worn outer flexible wheel sleeve 2 can be replaced. This significantly reduces the maintenance costs of the lawnmower robot, decreases waste generation, and improves resource utilization efficiency. Furthermore, the independently replaceable outer flexible wheel sleeves 2 shorten maintenance time, allowing the lawnmower robot to return to working condition more quickly and improving equipment efficiency.

[0045] In the above content, this embodiment proposes a scheme in which the inner hard tire 1 and the outer flexible wheel sleeve 2 can be connected in a detachable manner. However, in the process of its implementation, relative slippage may occur between the outer flexible wheel sleeve 2 and the inner hard tire 1, resulting in insufficient torque transmission and decreased walking stability.

[0046] In this embodiment, a first interlocking structure is provided on the outer periphery of the inner hard tire 1, and a second interlocking structure that cooperates with the first interlocking structure is provided on the inner periphery of the outer flexible wheel sleeve 2. The first interlocking structure and the second interlocking structure cooperate through friction and / or snap-fit ​​to suppress relative slippage and realize torque transmission.

[0047] Specifically, the aforementioned friction fit refers to the generation of sufficient static friction on the contact surface between the first and second interlocking structures to resist the tendency of relative motion, thereby transmitting torque. Friction fit can be achieved by selecting materials with a high coefficient of friction, increasing the contact area, or applying a preload.

[0048] A snap-fit ​​connection refers to a mechanical connection formed by the engagement or locking of protrusions and grooves in a mechanical structure to prevent relative slippage. Snap-fit ​​connections are achieved through the tight fitting of protrusions and grooves.

[0049] Suppressing relative slip means that by using the above-mentioned interlocking structure and cooperation method, the inner hard tire 1 and the outer flexible wheel sleeve 2 are effectively prevented from rotating relative to each other or moving axially during operation. This allows the rotational torque received by the inner hard tire 1 from the hub or drive shaft to be efficiently and reliably transmitted to the outer flexible wheel sleeve 2, enabling it to drive the lawnmower robot to walk.

[0050] The first interlocking structure is a mechanical connection feature located on the outer surface of the inner hard tire 1, which provides a fixed, force-transmitting contact surface for the outer flexible wheel sleeve 2. This structure can be one or a combination of two or more of the following: circumferentially distributed protrusions, grooves, toothed structures, keyways, or surface textures with specific geometric shapes. The second interlocking structure is a mechanical connection feature located on the inner surface of the outer flexible wheel sleeve 2, designed to match the first interlocking structure and form a tight connection to achieve force transmission between them. This structure can be a groove corresponding to a protrusion of the first interlocking structure, or a protrusion corresponding to a groove of the first interlocking structure, or a structure matching a key that mates with a keyway.

[0051] In this embodiment, a snap-fit ​​engagement method of the first interlocking structure and the second interlocking structure is illustrated, such as... Figure 2 and Figure 3 As shown, the inner hard tire 1 has multiple circumferentially spaced first grooves 11 on its inner circumference. These first grooves 11 are used to engage with protrusions on the outer circumference of the hub 3, so that the torque on the hub 3 can be transmitted to the inner hard tire 1. The outer circumference of the inner hard tire 1 has multiple circumferentially spaced first protrusions 12, and the inner circumference of the outer flexible wheel sleeve 2 has multiple circumferentially spaced second grooves 21. The first protrusions 12 engage with the second grooves 21, thereby realizing the force transmission between the two. When using this interlocking structure, when installing the outer flexible wheel sleeve 2, the user can push the outer flexible wheel sleeve 2 from the outside of the inner hard tire 1 to make it fit on the outer circumferential surface of the inner hard tire 1. In the above example, a block-shaped protrusion structure and a rectangular cross-section groove are shown.

[0052] In other embodiments, a second snap-fit ​​engagement method is exemplified for the first interlocking structure and the second interlocking structure, such as... Figure 4 As shown, the first protrusion 12 can be designed as a T-shaped protrusion and the second groove 21 can be designed as a T-shaped groove. The T-shaped protrusion and the T-shaped groove can not only fit together to realize force transmission, but also form a snap connection, which is beneficial to strengthen the connection strength between the inner hard tire 1 and the outer flexible wheel sleeve 2 and enhance the anti-skid performance.

[0053] In other embodiments, a third snap-fit ​​engagement method is exemplified for the first interlocking structure and the second interlocking structure, such as... Figure 5 As shown, the outer periphery of the inner hard tire 1 is provided with a third groove 13 distributed in a circumferential direction, and the inner periphery of the outer flexible wheel sleeve 2 is provided with a second protrusion 22 distributed in a circumferential direction. The second protrusion 22 and the third groove 13 are fitted together to realize the force transmission between the two.

[0054] In the above embodiments, some implementations of the interlocking structure extending axially along the inner hard tire 1 and the outer flexible wheel sleeve 2 are shown. It should be noted that in other embodiments, the interlocking structure may also extend circumferentially along the weed guard wheel 10, for example, as shown in... Figure 6 and Figure 7 As shown, a fourth groove 14 (i.e., annular groove) extending circumferentially is provided on the outer circumferential surface of the inner hard tire 1, and a third protrusion 23 (i.e., annular protrusion) extending circumferentially is provided on the inner circumferential surface of the outer flexible wheel sleeve 2. The third protrusion 23 is engaged with the fourth groove 14. This interlocking structure can prevent axial slippage between the inner hard tire 1 and the outer flexible wheel sleeve 2, and prevent the outer flexible wheel sleeve 2 from detaching from the inner hard tire 1. Furthermore, since both sides of the outer flexible wheel sleeve 2 are limited by the groove walls on both sides of the fourth groove 13, deformation of a certain area of ​​the outer flexible wheel sleeve 2 (i.e., the part limited by the groove walls) can be prevented to a certain extent, which can enhance the strength of the outer flexible wheel sleeve 2 to a certain extent and play a role in adjusting the structural strength of the outer flexible wheel sleeve 2.

[0055] Furthermore, such as Figure 8 and Figure 9 As shown, based on the above embodiment, a fourth protrusion 15 can be provided on the outer peripheral surface of the inner hard tire 1, and a fifth groove 24 can be provided on the inner peripheral surface of the outer flexible wheel sleeve 2. The fourth protrusion 15 and the fifth groove 24 are fitted together to achieve an interlocking function, so that the inner hard tire 1 and the outer flexible wheel sleeve 2 are locked in both the circumferential and axial directions, and no slippage will occur in either the circumferential or axial directions.

[0056] In other embodiments, a frictional engagement method of the first interlocking structure and the second interlocking structure is exemplified, such as... Figure 10As shown, the outer periphery of the inner hard tire 1 is provided with a first friction pattern 16, and the inner periphery of the outer flexible wheel sleeve 2 is provided with a second friction pattern 28. The first friction pattern 16 and the second friction pattern 28 are closely fitted to each other, and the force is transmitted between them by relying on the static friction between them.

[0057] As can be seen from the above embodiments, the interlocking structure of this application provides mechanical resistance or locking, ensuring that when the lawn mower robot starts, accelerates, decelerates or turns, the rotation of the inner hard tire 1 can synchronously drive the rotation of the outer flexible wheel sleeve 2, thereby providing a stable driving force, effectively overcoming the relative slippage problem between the inner and outer layers, and ensuring the driving efficiency and stable operation of the lawn mower robot under various working conditions.

[0058] This application does not limit the specific structural form of the outer flexible wheel sleeve 2. As an example, one specific implementation is as follows: Figure 11 As shown, the outer flexible wheel sleeve 2 can be designed as a continuous ring structure, with its inner surface tightly fitted to the outer surface of the inner hard tire 1. When assembling with the inner hard tire 1, the outer flexible wheel sleeve 2 can be stretched to temporarily expand its inner diameter, and then fitted onto the outer circumference of the inner hard tire 1. Once the external force is released, the outer flexible wheel sleeve 2 will contract tightly due to its elastic restoring force, firmly clamping itself onto the inner hard tire 1. This tight fit not only ensures a reliable connection between the outer flexible wheel sleeve 2 and the inner hard tire 1, effectively suppressing relative slippage between them, but also efficiently transmits the torque provided by the inner hard tire 1 to the outer flexible wheel sleeve 2, and then to the grass for walking.

[0059] In another specific implementation, the outer flexible wheel sleeve 2 includes a strip-shaped wheel sleeve body 25 and mounting ports located at both ends of the wheel sleeve body 25. The mounting ports at both ends of the wheel sleeve body 25 are connected by buckles, locks, straps, or fasteners, so that the wheel sleeve body 25 is tightly clamped to the outer periphery of the inner hard tire 1. Figure 12 As shown, hooks 26 and buckles 27 are respectively provided at both ends of the wheel sleeve body 25. The hooks 26 hook into the buckles 27 to achieve a snap-fit ​​connection between the two ends of the wheel sleeve body 25. To ensure a tight clamping effect, the length of the wheel sleeve body 25 in its unconnected state can be slightly less than the outer circumference of the inner hard tire 1. In this way, after the snap-fit ​​connection is completed, the wheel sleeve body 25 will generate a certain preload, thereby tightly clamping the outer circumference of the inner hard tire 1. This connection method is not only convenient to install, but also allows for quick disassembly by simply releasing the snap-fit ​​connection when the outer flexible wheel sleeve 2 needs to be replaced.

[0060] As another specific implementation method, such as Figure 13 and Figure 14As shown, the outer flexible wheel sleeve 2 has a split structure, comprising multiple wheel sleeve modules 2a. Each wheel sleeve module 2a is connected to the inner hard tire 1 via a connector 2b (such as a magnetic assembly or Velcro). The split design of the outer flexible wheel sleeve 2 facilitates the assembly of the outer flexible wheel sleeve 2 with the inner hard tire 1. Furthermore, each wheel sleeve module 2a can be replaced individually, further reducing maintenance costs and complexity.

[0061] This application does not limit the specific materials of the inner hard tire 1 and the outer flexible wheel sleeve 2. To reflect the difference in hardness (or flexibility) between the two, this embodiment defines the inner hard tire 1 as having a first hardness and the outer flexible wheel sleeve 2 as having a second hardness, wherein the first hardness is greater than the second hardness. The inner hard tire 1 is mainly used to bear the weight of the entire machine and transmit drive torque. Its material hardness is preferably characterized by Shore A hardness, and its hardness range can be Shore A 60~85, preferably Shore A 65~80. This hardness range can ensure the structural strength, wear resistance and torque transmission stability of the inner hard tire 1 while avoiding excessive deformation of the inner hard tire 1 during operation. The outer flexible wheel sleeve 2 is mainly used for contact with the lawn, and its function is to reduce the compaction and damage to the lawn, while improving ground adaptability and shock absorption performance. When the outer flexible wheel sleeve 2 is made of an elastomer or a high-density microporous material, its hardness can be characterized by Shore A, with a hardness range of Shore A 20~45; when the outer flexible wheel sleeve 2 is made of foam or a low-density microporous material, its hardness can be characterized by Shore OO, with a hardness range of Shore OO 30~70. Through the above settings, the hardness of the outer flexible wheel sleeve 2 can be ensured to be significantly lower than that of the inner hard tire 1, thus forming a "hard inside, soft outside" structural feature.

[0062] For example, the material of the outer flexible wheel sleeve 2 can be flexible materials such as ethylene propylene diene monomer (EPDM) foam, expanded ethylene-vinyl acetate copolymer (EVA), foam, thermoplastic polyurethane (TPU), microporous polyurethane, and thermoplastic vulcanizate (TPV). Among them, the internal pores of EPDM foam and EVA can provide excellent cushioning and shock absorption performance, effectively dispersing contact pressure. Foam is a lightweight, soft, and highly resilient porous material, such as polyethylene foam, which can provide good energy absorption and a comfortable feel, while also possessing a certain degree of abrasion resistance. Thermoplastic polyurethane is a material with plastic processing characteristics, exhibiting excellent abrasion resistance, weather resistance, and tear resistance, and is easy to mold and process. Microporous polyurethane material is a polyurethane elastomer with a microporous structure, combining the excellent elasticity and strength of polyurethane. The microporous structure helps to provide good grip while maintaining lightweight design and effectively absorb impact. Thermoplastic vulcanized rubber possesses the excellent mechanical properties of traditional vulcanized rubber, such as high elasticity, resistance to compression deformation, and aging resistance. Under repeated stretching, compression, and bending stresses, it maintains good elastic recovery and exhibits excellent fatigue resistance. All of the above materials are flexible materials with elasticity and cushioning properties, meeting the functional requirements of the outer flexible wheel sleeve in terms of grass protection, shock absorption, and ground contact. They provide stable grip under various ground conditions, making them reasonable and feasible material choices. It should be noted that in practical applications, closed-cell structures or microporous elastomer materials with good wear resistance are preferred to reduce water absorption and improve wear life.

[0063] Furthermore, this application does not limit the specific structure of the outer flexible wheel sleeve 2. In this embodiment, the outer flexible wheel sleeve 2 is an integrally formed structure without internal subdivisions of structural layers. In other embodiments, the outer flexible wheel sleeve 2 may include multiple structural layers, each with different hardness, wherein the outermost structural layer has the lowest hardness (i.e., the highest flexibility).

[0064] The material of the inner hard tire 1 can be an elastic material with a certain hardness, such as carbon black reinforced natural rubber, synthetic butyl rubber, fiber reinforced rubber, high-hardness polyurethane, styrene-butadiene rubber (SBR), butadiene rubber (BR), or their blends. Carbon black reinforced natural rubber refers to adding carbon black as a reinforcing agent to the natural rubber matrix. Through the interaction between carbon black and the rubber molecular chains, the tensile strength, tear strength, abrasion resistance, hardness, and anti-aging properties of the rubber are significantly improved. This can be achieved by adding carbon black of different particle sizes and structures during the mixing process of natural rubber, and by controlling the amount and dispersion uniformity of the carbon black. Synthetic butyl rubber is a synthetic rubber copolymerized from isobutylene and a small amount of isoprene. It is characterized by excellent airtightness, heat resistance, aging resistance, ozone resistance, and shock absorption. It can be produced through polymerization, followed by vulcanization molding with the addition of vulcanizing agents, accelerators, and other additives. For example, halogenated butyl rubber (such as chlorinated butyl rubber or brominated butyl rubber) can be used to achieve faster vulcanization speed and better co-vulcanization performance. Fiber-reinforced rubber refers to rubber matrix reinforced with short or continuous fibers to improve tensile strength, tear strength, modulus, dimensional stability, and creep resistance. This can be achieved by adding short fibers (such as polyester, aramid, nylon, glass, or carbon fibers) during rubber compounding, or by impregnating rubber into continuous fiber fabrics. The fiber length, content, orientation, and interfacial bonding strength with the rubber matrix are key factors. High-hardness polyurethane is a high-performance polymer material with excellent abrasion resistance, tear resistance, and high elasticity. Styrene-butadiene rubber (SBR) combines the advantages of both butadiene and styrene monomers, exhibiting superior abrasion resistance compared to natural rubber, better chemical stability, and ease of mixing and processing. Polybutadiene rubber (BR) is currently the most elastic of all rubbers, possessing excellent abrasion resistance, flexural strength, and cold resistance, maintaining good performance even at low temperatures.

[0065] It should be noted that the outer flexible wheel sleeve 2 and the inner hard tire 1 can be made of a single material or multiple materials. As a preferred embodiment, the main material of the outer flexible wheel sleeve 2 is foam, with flexible fibers embedded circumferentially inside the foam, and the outer surface of the foam covered with a wear-resistant material. This wear-resistant material resists wear and effectively extends the service life of the outer flexible wheel sleeve 2, reducing maintenance costs associated with frequent replacements. The inner hard tire 1 is made of carbon black-reinforced natural rubber. Carbon black-reinforced natural rubber has good overall performance in terms of strength, wear resistance, and cost control, making it a suitable material for the inner hard tire 1. Carbon black-reinforced natural rubber significantly improves the hardness and wear resistance of the inner hard tire 1, making it less prone to deformation or wear during long-term use, thus providing stable structural support.

[0066] Please refer to Figure 15 This embodiment also proposes an outer flexible wheel sleeve 2, which is fitted around the outer periphery of the tire 1' of the lawnmower robot. The tire 1' refers to a conventional tire used in existing lawnmower robots, and the tire 1' is connected to the hub 20. The outer flexible wheel sleeve 2 is made of a flexible material with a lower hardness than the tire 1'. When assembling with the tire 1', the outer flexible wheel sleeve 2 can be stretched to temporarily expand its inner diameter, and then fitted around the outer periphery of the tire 1'. Once the external force is released, the outer flexible wheel sleeve 2 will contract tightly due to its elastic restoring force, firmly clamping itself onto the tire 1'. This tight fit not only ensures a reliable connection between the outer flexible wheel sleeve 2 and the tire 1', effectively suppressing relative slippage between them, but also efficiently transmits the torque provided by the tire 1' to the outer flexible wheel sleeve 2, and then to the lawn to enable movement.

[0067] Please refer to Figure 16 This embodiment also proposes a lawn mowing robot 100, including a walking mechanism, which is provided with any of the lawn-protecting wheels 10 in the above embodiments of this application.

[0068] A lawnmower robot 100 is a mechanical device used for mowing lawns, whose main function is to efficiently and evenly cut grass vegetation. A lawnmower robot typically consists of a power source, a cutting device, a locomotive mechanism, and a control system. It can be self-propelled or ride-on to adapt to the mowing needs of lawns of different sizes and terrains. The locomotive mechanism is the key component for the lawnmower robot's mobility, responsible for supporting the robot body and providing driving force. The locomotive mechanism typically includes a frame, wheels, a drive motor or engine, and a transmission system. The lawn-protecting wheel 10 is a specially designed wheel proposed in this application, the core of which lies in optimizing the contact effect with the lawn through a double-layer structure.

[0069] When the lawnmower robot 100 starts and moves, the walking mechanism drives the grass-protecting wheels 10 to rotate. The outer flexible wheel sleeve 2 of the grass-protecting wheels 10 directly contacts the lawn, and its flexible deformation absorbs part of the impact force and disperses the pressure on the lawn, reducing damage. By integrating the grass-protecting wheels 10 into the walking mechanism of the lawnmower robot 100, this application can fully utilize the advantages of the grass-protecting wheels 10, significantly improving the protection effect on the lawn without sacrificing walking performance. At the same time, the outer flexible wheel sleeve 2 deforms under the pressure of the lawnmower robot's own weight, which can increase the contact area with the lawn, provide sufficient friction to cope with slippery ground, achieve a track-like function, and improve the stability of the lawnmower robot in complex terrain.

[0070] Because the lawnmower wheel 10 has a large diameter, and the battery of the lawnmower robot 100 is usually located at one end of the body, in some cases, the other end of the body may be tilted up, causing the wheel to dangle. To avoid this situation, this embodiment has a counterweight at the end of the lawnmower robot 100 away from the battery to reduce the weight difference between the two ends of the body, so that the center of gravity of the body is in the middle position, preventing one end of the body from tilting up.

[0071] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application; the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance; furthermore, unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections, or integral connections; they can be direct connections or indirect connections through an intermediate medium, and they can be internal connections between two components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0072] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lawn-protecting wheel for a lawn-mowing robot, characterized in that, It includes an inner hard tire and an outer flexible wheel sleeve. The inner hard tire is connected to the wheel hub or drive shaft to provide structural support and torque output. The outer flexible wheel sleeve is made of flexible material and is fitted around the outer periphery of the inner hard tire, making direct contact with the grass.

2. The weed protection wheel according to claim 1, characterized in that, The inner hard tire has a first interlocking structure on its outer periphery, and the outer flexible wheel sleeve has a second interlocking structure on its inner periphery that cooperates with the first interlocking structure. The first interlocking structure and the second interlocking structure cooperate through friction and / or snap-fit ​​to suppress relative slippage and achieve torque transmission.

3. The weed protection wheel according to claim 1 or 2, characterized in that, The outer flexible wheel sleeve is detachably connected to the inner hard tire, and the outer flexible wheel sleeve can be replaced independently.

4. The weed protection wheel according to claim 1 or 2, characterized in that, The inner hard tire has a first hardness, and the outer flexible wheel sleeve has a second hardness, wherein the first hardness is greater than the second hardness.

5. The weed protection wheel according to claim 1 or 2, characterized in that, The outer flexible wheel sleeve is an integral structure, and it is fitted onto the outer periphery of the inner hard tire by elastic extension.

6. The weed protection wheel according to claim 1 or 2, characterized in that, The outer flexible wheel sleeve includes a strip-shaped wheel sleeve body and mounting ports located at both ends of the wheel sleeve body. The mounting ports at both ends of the wheel sleeve body are connected by buckles, locks, pull straps or fasteners, so that the wheel sleeve body is tightly clamped to the outer periphery of the inner hard tire.

7. The weed protection wheel according to claim 1 or 2, characterized in that, The outer flexible wheel sleeve has a split structure, and the outer flexible wheel sleeve includes multiple wheel sleeve modules. Each wheel sleeve module is connected to the inner hard tire through a connector.

8. The weed protection wheel according to claim 1 or 2, characterized in that, The outer flexible wheel sleeve includes multiple structural layers, each with a different hardness, with the outermost structural layer having the lowest hardness.

9. A flexible outer wheel sleeve for mounting on the outer circumference of the tires of a lawnmower robot; characterized in that, The outer flexible wheel sleeve is made of a flexible material with a hardness lower than that of the tire.

10. A lawnmower robot, characterized in that, It includes a walking mechanism, which is provided with a grass-protecting wheel as described in any one of claims 1 to 8.

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