Drive system and mower

Abstract

The application provides a driving system and a mower. The driving system comprises a motor, a clutch and a moving wheel. The clutch comprises at least a first gear and a second gear, and the first gear and the second gear are engaged in a direction perpendicular to the ground or in a direction parallel to the ground. The moving wheel comprises a steering shaft, and the steering shaft is connected with the clutch. The clutch is arranged between the motor and the steering shaft. The clutch has a first state and a second state. In the first state, the power of the motor can be transmitted to the steering shaft. In the second state, the clutch cuts off the power transmission between the motor and the steering shaft. In the driving system provided by the application, the clutch can switch states. When an impact force is applied, the clutch cuts off the power transmission, effectively mitigates the damage caused by the impact force to the driving system, avoids the damage to the internal gears, and reduces the risk of damage and failure of the driving system when falling.

Description

Technical Field

[0001] This application relates to the field of garden tool technology, and in particular to a drive system and a lawnmower. Background Technology

[0002] A lawnmower is a tool used to trim lawns, vegetation, etc. It has a cutting device at the bottom to cut and trim the lawn.

[0003] Existing lawnmowers typically use a steering motor gearbox with a rigid drive chain design to achieve steering. However, when such lawnmowers are subjected to impacts and falls, the gears, bearings, and other transmission components inside the gearbox are subjected to enormous inertial impact forces, which can easily lead to irreversible damage such as broken teeth and bent shafts. Utility Model Content

[0004] In view of this, the purpose of this application is to propose a drive system that can effectively mitigate the damage caused by impact force to the drive system and reduce the risk of damage and failure of the drive system during a drop.

[0005] To achieve one of the above objectives, this application provides a driving system comprising:

[0006] Electric motor;

[0007] The clutch includes at least one first gear and a second gear, which mesh in a direction perpendicular to the ground or in a direction parallel to the ground;

[0008] A movable wheel, including a steering shaft, the steering shaft being connected to the clutch;

[0009] The clutch is disposed between the motor and the steering shaft; wherein the clutch has a first state and a second state, in the first state, the power of the motor can be transmitted to the steering shaft; in the second state, the clutch disconnects the power transmission between the motor and the steering shaft.

[0010] Optionally, in the second state, the clutch engages in a direction perpendicular to the ground.

[0011] Optionally, the first gear is fixedly sleeved on a rotating shaft; the second gear is sleeved on the rotating shaft, and the second gear is movable relative to the rotating shaft;

[0012] The first gear meshes with the second gear, and the meshing force exerted by the tooth surface of the first gear on the teeth of the second gear includes a component perpendicular to the ground.

[0013] When the component is greater than a preset value, the clutch is in the second state; when the component is less than the preset value, the clutch is in the first state. In the first state, the first gear and the second gear remain relatively stationary in a direction perpendicular to the ground. In the second state, the second gear is displaced relative to the first gear in a direction perpendicular to the ground.

[0014] Optionally, the clutch further includes:

[0015] An elastic element is located on the side of the second gear away from the first gear. The first end of the elastic element is fixedly connected to the rotating shaft, and the second end abuts against the second gear. The preset value is the magnitude of the torque generated by the elastic element.

[0016] Optionally, the torque generated by the elastic element is in the range of 2-20 N / M.

[0017] Optionally, the drive system further includes at least one transmission gear disposed between the clutch and the moving wheel; and / or, the transmission gear is disposed between the motor and the clutch.

[0018] Optionally, the transmission gear is connected to the output shaft of the motor and meshes with the first gear; and / or, the transmission gear is connected to the steering shaft and meshes with the second gear.

[0019] Optionally, the pitch circle diameter of the first gear is smaller than that of the second gear.

[0020] Optionally, the clutch further includes:

[0021] A fixed base is disposed on the rotating shaft and is fixedly connected to the first end of the elastic member.

[0022] On the other hand, this application also provides a lawnmower, which includes a housing and a working mechanism at the bottom of the housing for performing cutting tasks; the lawnmower also includes the aforementioned drive system, which is disposed inside the housing and drives the moving wheels on both sides of the housing to turn.

[0023] In the drive system provided in this application, the clutch includes at least one first gear and a second gear, which mesh in a direction perpendicular to the ground or parallel to the ground. The moving wheel includes a steering shaft, which is connected to the clutch. The clutch is positioned between the motor and the steering shaft. The clutch has a first state and a second state. In the first state, power from the motor can be transmitted to the steering shaft. In the second state, the clutch disconnects the power transmission between the motor and the steering shaft. The drive system provided in this application allows the clutch to switch states. When subjected to impact, the clutch disconnects the power transmission, effectively mitigating damage to the drive system caused by the impact, preventing damage to internal gears, and reducing the probability of damage and failure of the drive system during drops, thereby improving the stability and practicality of the drive system. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a lawnmower according to one embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the structure of a movable wheel according to an embodiment of this application;

[0027] Figure 3 This is a schematic diagram of the structure of a drive system according to an embodiment of this application;

[0028] Figure 4 for Figure 3 Exploded view of the drive system;

[0029] Figure 5 This is a schematic diagram of the clutch in a first state according to an embodiment of this application;

[0030] Figure 6 This is a schematic diagram of the clutch in a second state according to an embodiment of this application.

[0031] The symbols in the attached image are explained as follows:

[0032] 100. Drive system; 10. Motor; 11. Output shaft; 20. Clutch; 21. First gear; 22. Second gear; 23. Rotating shaft; 24. Elastic element; 25. Fixed seat; 31. Steering shaft; 40. Transmission gear; 1000. Lawn mower; 200. Housing; 300. Casters. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0034] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in some embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "inner," "outer," and "front" 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.

[0035] Current lawnmowers often employ differential steering. In this system, the drive motor is connected to the drive shaft of the moving wheels via flexible or semi-rigid transmission structures such as gear sets and drive shafts. The drive motor features differential matching, allowing the moving wheels to steer based on their speed difference. The torque output from the drive motor is stably transmitted to the moving wheels without interference between the motor and the wheels due to their steering motion. Therefore, the drive motor can provide power for both the movement and steering of the moving wheels. However, differential steering often leads to wear and tear on the lawn, compromising its aesthetics.

[0036] Therefore, to reduce grass abrasion, most existing lawnmowers adopt an active steering system, which incorporates a steering motor to control the active steering of the drive wheels. In this active steering system, the movement of the drive wheels is powered by a drive motor, while the steering of the drive wheels is powered by a steering motor. The drive motor is typically mounted between the steering shaft and the wheel body, allowing the steering motor to turn the steering shaft while simultaneously driving the drive motor to move the drive wheels.

[0037] However, in the event of an accident such as a fall, the active steering structure often experiences a greater impact than the differential steering structure. This is because the differential steering system lacks an independent steering component; it relies solely on the drive motor to drive the moving wheels through the transmission assembly. The impact force has a long transmission path, and without an additional steering structure to absorb the impact, the resulting impact force is relatively small. In contrast, active steering requires an additional independent steering mechanism, such as a steering motor. These components are often located near the wheel wells, are lightweight, and upon impact, the impact force is directly and unimpededly transmitted to the steering mechanism through the moving wheels, causing it to directly bear the load.

[0038] The inventors discovered that existing lawnmower steering motors and gearboxes typically employ a rigid transmission chain design. A typical gearbox structure includes an input shaft, a gear set, and an output shaft. The input shaft is directly connected to the motor output. The gear set is a multi-stage reduction gear, such as planetary gears or helical gears. The output shaft drives external loads, such as robot joints and wheels. For compact robots with limited internal space, the transmission gear set needs to be made more delicate and lightweight. Therefore, the rigid transmission chain is prone to breakage upon external impact.

[0039] Traditional protection measures for the steering mechanism in lawnmowers mainly include three types. First, increasing gear thickness and using high-strength materials (such as carburized steel) to resist impact and strengthen the structure. Second, filling the gearbox with cushioning materials, adding rubber pads or energy-absorbing foam inside the gearbox housing. Third, installing mechanical safety pins, creating shear-type weak points in the transmission chain, which break under overload to protect core components.

[0040] However, in the first scenario, the gearbox's internal transmission components, such as gears and bearings, experience tremendous inertial impact upon impact. The rigid connection cannot actively cut off the power transmission path, making irreversible damage such as broken teeth and bent shafts likely. In the second scenario, the cushioning material can only absorb a portion of the energy and cannot prevent internal collisions caused by the gear set continuing to rotate due to inertia, thus failing to avoid a "hard collision." In the third scenario, the shear-type safety pin requires frequent replacement, resulting in high maintenance costs and impacting the continuous operation of the equipment.

[0041] Based on this, this application provides a driving system 100 to solve the above-mentioned technical problems.

[0042] like Figures 1-5 As shown, this application embodiment provides a driving system 100, see [link to relevant documentation]. Figure 1 and Figure 2The drive system 100 includes a motor 10, a clutch 20, and a moving wheel 300. The clutch 20 includes at least one first gear 21 and a second gear 22, which mesh in a direction perpendicular to or parallel to the ground. The moving wheel 300 includes a steering shaft 31 connected to the clutch 20. The clutch 20 is positioned between the motor 10 and the steering shaft 31. The clutch 20 has a first state and a second state. In the first state, power from the motor 10 can be transmitted to the steering shaft 31. In the second state, the clutch 20 disconnects the power transmission between the motor 10 and the steering shaft 31.

[0043] In the drive system 100 of this application embodiment, by setting a switchable clutch 20, when subjected to an impact force, the clutch 20 cuts off the power transmission, which can effectively mitigate the damage caused by the impact force to the drive system 100, avoid damage to the internal gears, reduce the probability of damage and failure of the drive system 100 when falling, and thus improve the stability and practicality of the drive system 100.

[0044] When the drive system 100 is working normally, the motor 10 provides steering power and transmits the power to the steering shaft 31 through the clutch 20, thereby realizing the active steering of the moving wheel 300. When a fall from a height or external impact occurs, the moving wheel 300 in the drive system 100 is impacted first and transmits the impact force to the clutch 20 in the reverse direction.

[0045] In some embodiments, reference Figure 2 The structure that drives the movable wheel 300 to steer is located above the structure that drives the movable wheel 300 to move. The drive motor is mounted on the lower part of the steering shaft 31 via a mounting bracket. The drive motor is used to drive the movable wheel 300 to rotate about its horizontal axis. The motor 10 is used to drive the steering shaft 31 to rotate about its vertical axis.

[0046] refer to Figure 5 When the drive system 100 is working normally, the clutch 20 is in the first state, the first gear 21 and the second gear 22 maintain stable meshing, and the power output by the motor 10 is smoothly transmitted to the clutch 20 through gear meshing, and then transmitted from the clutch 20 to the steering shaft 31 of the moving wheel 300, ultimately driving the moving wheel 300 to rotate.

[0047] refer to Figure 6In the event of an accident such as a fall by the lawnmower 1000, the drive system 100 is impacted by an external force. The moving wheel 300 rotates under this force, which in turn drives the steering shaft 31 to rotate. The steering shaft 31 exerts a force on the gear it meshes with. At this time, the second gear 22 receives the external force transmitted through the steering shaft 31, either directly or indirectly. In its second state, the clutch 20 actively disengages from the first gear 21 under the influence of the external force, thus disengaging the gear and completely cutting off the power transmission path between the motor 10 and the moving wheel 300. This transforms the rigid, non-disconnectable power transmission path in the existing design into a controllable on / off path. By switching the state of the clutch 20, power transmission is ensured under normal operating conditions, and power is quickly cut off under abnormal operating conditions, preventing impact energy from being transmitted into the drive system 100.

[0048] Compared to existing solutions that "strengthen structural strength", the impact force in this drive system 100 cannot be transmitted to core components such as gears and bearings through the broken transmission path, thus avoiding irreversible damage such as broken teeth and bent shafts.

[0049] Compared to the existing passive solution of "buffer material filling", the rotation of the gear set in the drive system 100 due to inertia will be rapidly decelerated due to the interruption of power transmission, and no internal "hard collision" will occur, resulting in a more thorough energy absorption effect.

[0050] Compared to the existing "shear-type safety pin" solution, the clutch 20 in this drive system 100 does not require sacrificial replacement like a mechanical safety pin when switching states. It can simply restore gear engagement after troubleshooting, which greatly reduces maintenance costs and ensures continuous operation of the equipment.

[0051] In some embodiments of this application, the first gear 21 and the second gear 22 mesh in a direction perpendicular to the ground, that is, the axes of the first gear 21 and the second gear 22 are both perpendicular to the ground, which can be adapted to the installation space of the "vertical structure" and save horizontal space.

[0052] In some embodiments of this application, the first gear 21 and the second gear 22 mesh in a direction parallel to the ground, that is, the axes of the first gear 21 and the second gear 22 are both parallel to the ground, which can be adapted to the installation space of the "flat structure" without occupying too much height and saving height space.

[0053] Both of the above meshing methods belong to parallel axis meshing, which can be adapted to different installation spaces and power transmission direction requirements. Compared with meshing methods that change the power direction (e.g., from horizontal to vertical), they have simpler structures, lower costs, higher transmission efficiency, and less wear loss.

[0054] Normally, the direction perpendicular to the ground is the transmission path where impact energy is most concentrated under abnormal operating conditions such as equipment drops and vibrations. When equipment falls accidentally, gravity will drive the equipment to collide with the ground in a vertical direction. The impact force generated by the collision will be transmitted vertically upward to the moving wheel 300, and then transmitted to the internal components of the gearbox through the steering shaft 31.

[0055] When the drive system 100 is subjected to an impact force, the first gear 21 and the second gear 22 of the clutch 20 will separate in the vertical direction, directly cutting off the power and impact inertia transmitted between the moving wheel 300 and the motor 10 along the vertical path. In this way, the main direction of impact energy transmission can be precisely targeted, and the power can be interrupted before the impact load is transmitted to the internal components of the gearbox. This can effectively mitigate the damage caused by the impact force to the drive system 100, avoid damage to the internal gears, and reduce the probability of damage and failure of the drive system 100 during a drop.

[0056] In some embodiments of this application, see Figure 5 and Figure 6 The first gear 21 can be fixedly mounted on a rotating shaft 23. The second gear 22 is mounted on the rotating shaft 23 and can move relative to the rotating shaft 23. The first gear 21 and the second gear 22 mesh, and the meshing force exerted by the tooth surface of the first gear 21 on the teeth of the second gear 22 includes a component perpendicular to the ground.

[0057] When the component is less than a preset value, the clutch 20 is in a first state, in which the first gear 21 and the second gear 22 remain relatively stationary in a direction perpendicular to the ground. When the component is greater than the preset value, the clutch 20 is in a second state, in which the second gear 22 is displaced relative to the first gear 21 in a direction perpendicular to the ground.

[0058] Here, the first gear 21 is fixedly mounted on the rotating shaft 23, meaning that there is no relative movement between the first gear 21 and the rotating shaft 23, and power can be stably transmitted to the first gear 21. The second gear 22 is also mounted on the rotating shaft 23, but it can move relative to the rotating shaft 23, reserving space for subsequent vertical displacement.

[0059] In the first normal operating state, the clutch 20 operates smoothly, and the power transmitted by the motor 10 causes the vertical component of the meshing force generated by the meshing of the two gears to be less than a preset value. At this time, although the second gear 22 can move relative to the rotating shaft 23, it will not undergo significant displacement under the action of the small vertical component, and remains relatively stationary with the first gear 21 in the direction perpendicular to the ground. The power can be transmitted from the rotating shaft 23 to the steering shaft 31 of the subsequent moving wheel 300 through the stable meshing of the two gears, ensuring normal drive.

[0060] When abnormal operating conditions such as drops or overloads occur, the impact or overload will cause a sharp change in the force on the meshing of the two gears. The vertical component of the meshing force exceeds the preset value, and the clutch 20 switches to the second state. At this time, the vertical component exceeding the preset value will drive the movable second gear 22 to displace relative to the fixed first gear 21 in a direction perpendicular to the ground, thereby breaking the effective meshing of the two gears. This interrupts the originally continuous power transmission path due to the vertical displacement of the gears, and the power transmission between the motor 10 and the moving wheel 300 is interrupted. This can effectively mitigate the damage caused by the impact force to the drive system 100, prevent damage to the internal gears, and reduce the probability of damage and failure of the drive system 100 during drops.

[0061] In some specific embodiments, see Figure 5 and Figure 6 The meshing surface between the teeth of the second gear 22 and the first gear 21 is an inclined surface. When the drive system 100 is impacted, the second gear 22 moves downward and disengages from the first gear 21, thereby interrupting the transmission of force and achieving the purpose of unloading energy.

[0062] In some embodiments of this application, the pitch circle diameter of the first gear 21 may be smaller than the pitch circle diameter of the second gear 22.

[0063] It's understandable that the pitch circle is an imaginary circle on a gear, and its diameter is calculated based on the gear's basic parameters (module, number of teeth). When a pair of gears are correctly meshed, their pitch circles will be tangent. The formula for calculating the pitch circle diameter (d) is: d = m × z. Where: m is the module; the larger the module, the larger the gear size and the stronger its load-bearing capacity; z is the number of teeth, the number of teeth on the gear.

[0064] The pitch circle diameter of the first gear 21 (driving gear) is smaller than that of the second gear 22 (driven gear). The smaller gear drives the larger gear to achieve speed reduction meshing. Under normal operating conditions, the power of the motor 10 is transmitted to the first gear 21 via the rotating shaft 23. Because the pitch circle diameter of the first gear 21 is smaller, when its number of teeth rotating per unit time matches that of the second gear 22, it will drive the second gear 22 to rotate at a lower speed through the meshing relationship, thus achieving speed reduction and torque increase.

[0065] At this time, the vertical component of the meshing force generated by the meshing of the two gears is determined by the transmitted torque. Because the pitch circle diameter of the first gear 21 is small, under the same input torque, the circumferential force at the meshing point is more easily controlled within the preset value when it is converted into the vertical component, so that the second gear 22 remains relatively stationary, ensuring that the power is stably transmitted to the steering shaft 31.

[0066] When the equipment encounters abnormal conditions such as drops or overloads, the impact load will cause the moving wheel 300 or the steering shaft 31 to generate an instantaneous reverse torque, which is transmitted to the meshing point through the second gear 22. Because the pitch circle diameter of the second gear 22 is larger, it will convert the impact torque into a larger meshing point force when it is subjected to the reverse impact torque.

[0067] Since the meshing force of the two gears includes a vertical component, a larger meshing force will directly cause the vertical component to exceed the preset value. At this time, the movable second gear 22 will be displaced in the vertical direction relative to the fixed first gear 21, breaking the meshing relationship, thereby blocking the transmission of impact torque to the motor 10 and transmission components, and preventing damage to the components of the drive system 100.

[0068] In some embodiments of this application, reference is made to Figure 5 and Figure 6 The clutch 20 may also include an elastic element 24, which is located on the side of the second gear 22 away from the first gear 21. The first end of the elastic element 24 is fixedly connected to the rotating shaft 23, and the second end abuts against the second gear 22. The preset value is the magnitude of the torque generated by the elastic element 24.

[0069] In this way, the elastic element 24 always applies a preload force to the second gear 22 along the direction of the rotation axis 23, which is then converted into an elastic torque that resists the displacement of the second gear 22, and the magnitude of this torque is the preset value for the switching of the clutch 20. The elastic element 24 can provide a precise and quantifiable mechanical control basis for the switching of the clutch 20 state, so that the "preset value of the component of the meshing force in the direction perpendicular to the ground" is converted into an "elastic torque" that can be set by the parameters of the elastic element 24.

[0070] In the first state, the clutch 20, powered by the motor 10, causes a small component of the meshing force in the direction perpendicular to the ground when the first gear 21 and the second gear 22 mesh, resulting in a torque less than the preload torque of the elastic element 24. At this time, the abutting force of the elastic element 24 is sufficient to limit the displacement of the second gear 22 along the rotation shaft 23, ensuring stable meshing between the first and second gears. Power can then be smoothly transmitted through the gear set to the steering shaft 31 of the moving wheel 300, meeting the normal driving requirements of the equipment.

[0071] In the second state, when the drive system 100 is impacted, the impact force will cause the moving wheel 300 to generate an instantaneous reverse force. This force is transmitted to the meshing point through the second gear 22, causing the vertical component of the meshing force between the first gear 21 and the second gear 22 to increase sharply, and the corresponding torque exceeds the preload torque of the elastic element 24.

[0072] At this point, the resisting force of the elastic element 24 can no longer restrict the displacement of the second gear 22. The second gear 22 will move away from the first gear 21 along the rotating shaft 23, compressing the elastic element 24 and disengaging from the first gear 21. This cuts off the power transmission path between the motor 10 and the moving wheel 300, preventing the impact load from being transmitted to the components inside the drive system 100, thus avoiding irreversible damage.

[0073] When the impact force is released, the torque corresponding to the vertical component of the meshing force returns to below the preload torque of the elastic element 24. The elastic element 24 will push the second gear 22 to reset under its own elastic force, re-engage with the first gear 21, and return the clutch 20 to the first state. Power transmission can be restored without manual intervention.

[0074] In some embodiments, the elastic element 24 may be a spring. In other embodiments, the elastic element 24 may also be other elastic structures, such as an elastic block, an elastic sheet, etc.

[0075] In some embodiments of this application, the torque generated by the elastic element 24 can be in the range of 2-20 N / M, for example, 2 N / M, 5 N / M, 10 N / M, 15 N / M, 20 N / M, etc. The torque value is adapted to the weight of the machine. The torque range in this embodiment can cover machines weighing 10-60 kg. The greater the weight of the machine, the greater the torque generated by the elastic element.

[0076] Under normal operating conditions, the meshing torque corresponding to the power transmitted from the motor 10 to the gear set of the clutch 20 is generally below 2 N / m. The upper limit of 20 N / m sets a safety redundancy range for the protection function of the drive system 100. This torque range satisfies the driving force required for the steering of the moving wheel 300 (such as driving the equipment steering shaft 31 to rotate and coping with daily ground friction resistance), and also ensures that the preload of the elastic element 24 stably limits the displacement of the second gear 22, so that the first gear 21 and the second gear 22 remain engaged, and the power can be smoothly transmitted to the moving wheel 300. This avoids the clutch being accidentally triggered during normal operation due to the preset torque being too low, or the overload not being protected in time due to the preset torque being too high.

[0077] When the drive system 100 is subjected to an impact, the impact force will cause the steering shaft 31 of the moving wheel 300 to generate an instantaneous reverse torque, which is transmitted to the meshing point of the first gear 21 and the second gear 22 through the second gear 22. If this reverse torque is lower than the torque generated by the elastic element 24, the preload of the elastic element 24 will not be able to prevent the displacement of the second gear 22. At this time, the second gear 22 will move away from the first gear 21 along the rotation shaft 23, and the second gear 22 will disengage from the first gear 21, cutting off the power transmission path between the motor 10 and the moving wheel 300, preventing the impact torque from being transmitted to the components inside the drive system 100, and preventing damage to the components.

[0078] When the abnormal working condition is resolved, the reverse torque disappears, and the meshing force of the tooth surface of the first gear 21 acting on the teeth of the second gear 22 returns to a preset value in the direction perpendicular to the ground. The elastic element 24 will push the second gear 22 to reset under its own elastic force, so that the first gear 21 and the second gear 22 re-mesh and transmit power.

[0079] In some embodiments of this application, reference is made to Figure 5 and Figure 6 The clutch 20 may also include a fixed seat 25, which is disposed on the rotating shaft 23 and is fixedly connected to the first end of the elastic member 24.

[0080] Here, the fixed seat 25 is sleeved on the rotating shaft 23 and fixedly connected to the first end of the elastic element 24. It can provide a stable fulcrum for the elastic element 24, better stabilize the elastic element 24, and prevent the elastic element 24 from sliding relative to the rotating shaft 23 when the impact force is greater than its clamping force on the rotating shaft 23. This ensures that the preload of the elastic element 24 can stably act on the second gear 22, thereby ensuring the reliability of the clutch 20 state switching.

[0081] Since the surface of the rotating shaft 23 is mostly a smooth cylindrical surface, directly fixing the elastic element 24 is prone to problems such as displacement and slippage. However, the fixed seat 25 can lock its position in the preset position of the rotating shaft 23 by fixing it to the rotating shaft 23, such as by key connection or interference fit. Then, by fixing it to the first end of the elastic element 24, the elastic element 24 can be stably installed.

[0082] In some embodiments of this application, reference is made to Figure 5 and Figure 6 The drive system 100 may also include at least one transmission gear 40, which is disposed between the clutch 20 and the movable wheel 300, and / or, the transmission gear 40 is disposed between the motor 10 and the clutch 20.

[0083] In other words, there can be one transmission gear 40, which can be located between the clutch 20 and the moving wheel 300 or between the motor 10 and the clutch 20.

[0084] The number of transmission gears 40 can be multiple, such as 2, 3, 4, 5, 6, etc. When there are multiple transmission gears 40, they can all be set between the clutch 20 and the moving wheel 300, or between the motor 10 and the clutch 20, depending on actual needs. Of course, the required number of transmission gears 40 can also be set separately between the clutch 20 and the moving wheel 300, and between the motor 10 and the clutch 20, depending on actual needs.

[0085] When a transmission gear 40 is installed between the clutch 20 and the moving wheel 300, the power output from the motor 10 is first controlled by the clutch 20 to switch on and off, and then enters the transmission gear 40 after engagement. The transmission gear 40 adapts the power to the motion requirements of the moving wheel 300 by adjusting the transmission ratio or changing the direction of power. For example, when the drive system 100 requires a large torque to overcome ground friction, the transmission gear 40 can amplify the torque transmitted by the clutch 20, making movement or steering easier. At the same time, the transmission gear 40 can convert rotational motion into the deflection angle required by the moving wheel 300.

[0086] In this way, clutch 20 can directly disconnect or connect power to the moving wheel 300. When turning, it engages with transmission gear 40 to transmit power, and disconnects when not turning, reducing power loss. The optimized gear ratio can specifically improve the power characteristics of the moving wheel 300, adapting to different terrains (such as requiring greater steering torque when the grass is bumpy). Furthermore, since transmission gear 40 is located downstream of clutch 20, it can prevent the reaction force of the moving wheel 300 from being directly transmitted to clutch 20 in the reverse direction, protecting clutch 20 from impact damage.

[0087] When a transmission gear 40 is installed between the motor 10 and the clutch 20, the transmission gear 40 completes a preliminary adaptation before the power enters the clutch 20, making the power output by the motor 10 more compatible with the working characteristics of the clutch 20. When the output parameters of the motor 10 (especially the high-speed, low-torque motor 10) do not match the optimal working range of the clutch 20, the transmission gear 40 can adjust the power to a range that the clutch 20 can more easily bear by reducing speed and increasing torque, and then the power is transmitted to subsequent components by the clutch 20.

[0088] This avoids the high-speed motor 10 directly acting on the clutch 20, reducing the sliding friction loss of the clutch 20 and extending its service life. The transmission gear 40 optimizes the power parameters in advance, resulting in less impact when the clutch 20 engages and improving the operational stability of the drive system 100.

[0089] In some embodiments of this application, the transmission gear 40 may be connected to the output shaft 11 of the motor 10, the transmission gear 40 may mesh with the first gear 21, and / or the transmission gear 40 may be connected to the steering shaft 31 of the moving wheel 300, and the transmission gear 40 may mesh with the second gear 22.

[0090] When the transmission gear 40 is connected to the output shaft 11 of the motor 10 and meshes with the first gear 21, the power output by the motor 10 is transmitted sequentially to the transmission gear 40 and the first gear 21 through the output shaft 11. The transmission gear 40 first performs preliminary torque and speed adjustment on the power of the motor 10, for example, by reducing speed and increasing torque or increasing speed and reducing torque as needed, and then transmits the appropriate power to the first gear 21.

[0091] When the transmission gear 40 is connected to the steering shaft 31 of the movable wheel 300 and meshes with the second gear 22, the power transmitted by the clutch 20 is sequentially transmitted to the transmission gear 40 and the steering shaft 31 of the movable wheel 300 through the second gear 22. The transmission gear 40 adjusts the power to the torque and speed suitable for the steering of the movable wheel 300. For example, when the movable wheel 300 needs to overcome ground friction, the transmission gear 40 can increase torque; when it needs to turn quickly, it can increase speed, thereby ensuring the efficient operation of the movable wheel 300.

[0092] Furthermore, when the drive system 100 is subjected to an impact, the moving wheel 300 generates a reverse inertial torque due to the impact. The meshing structure of the transmission gear 40 will attenuate the reverse torque through the friction damping effect, which can further improve the protection effect of the drive system 100.

[0093] refer to Figure 1 This application embodiment also provides a lawnmower 1000, which may include a housing 200, and a working mechanism is provided at the bottom of the housing 200 for performing cutting tasks. The lawnmower 1000 also includes the aforementioned drive system 100, which is disposed inside the housing 200 and drives the moving wheels 300 on both sides of the housing 200 to rotate.

[0094] This can be understood as follows: during normal mowing operations, the moving wheels 300 on both sides of the housing 200 need to flexibly turn according to the working path. The power of the motor 10 is transmitted to the steering shaft 31 through the first gear 21 and the second gear 22, driving the moving wheels 300 to turn precisely, while the working mechanism at the bottom of the housing 200 performs the cutting task synchronously.

[0095] When the lawnmower 1000 encounters abnormal outdoor conditions, such as when the moving wheel 300 rolls over a protruding rock and causes an impact, the moving wheel 300 generates an instantaneous reverse torque. This torque is transmitted to the second gear 22 via the steering shaft 31. At this time, the clutch 20 switches to the second state, and the second gear 22 displaces in a direction perpendicular to the ground, overcoming the preload force of the elastic element 24, and disengages from the first gear 21. The power transmission path between the motor 10 and the moving wheel 300 is cut off, and the reverse impact torque cannot be transmitted to the components of the motor 10 and the drive system 100, thus preventing the motor 10 from overloading and burning out, the gear from breaking teeth, or the steering shaft 31 from bending.

[0096] In some embodiments, the two movable wheels 300 located on both sides of the housing 200 can be controlled by the same drive system 100 for steering, which can improve the steering control accuracy.

[0097] In other embodiments, the two moving wheels 300 located on both sides of the housing 200 can be controlled by a drive system 100 to steer, which can reduce the number of drive systems 100, reduce the space occupied by the drive systems 100, and reduce the operating cost of the lawnmower 1000.

[0098] In the lawnmower 1000 of this application embodiment, the drive system 100 is disposed within a housing. The clutch 20 of the drive system 100 includes at least one first gear 21 and a second gear 22, which mesh in a direction perpendicular to the ground or parallel to the ground. The moving wheel 300 includes a steering shaft 31, which is connected to the clutch 20. The clutch 20 is disposed between the motor 10 and the steering shaft 31. The clutch 20 has a first state and a second state. In the first state, the power of the motor 10 can be transmitted to the steering shaft 31. In the second state, the clutch 20 disconnects the power transmission between the motor 10 and the steering shaft 31. The drive system 100 provided in this application has a switchable state for the clutch 20. When subjected to impact, the clutch 20 disconnects the power transmission, which can effectively mitigate the damage caused by the impact to the drive system 100, avoid damage to internal gears, and reduce the probability of damage and failure of the drive system 100 during a fall, thereby improving the stability and practicality of the drive system 100.

[0099] In some embodiments of this application, the clutch 20 may be a mechanical clutch or an electromagnetic clutch.

[0100] A mechanical clutch achieves engagement and disengagement through direct contact and separation of mechanical structures. As described above, a mechanical clutch transmits torque through the meshing of teeth, causing the driving and driven shafts to rotate synchronously. Mechanical clutches are simple in structure, highly reliable, require no additional energy source, can withstand large torque and impact loads, and have low maintenance costs.

[0101] An electromagnetic clutch utilizes the magnetic force generated by electromagnetic induction to achieve engagement and disengagement. It mainly consists of an electromagnetic coil, an armature, and friction plates. When the coil is energized, the generated electromagnetic force attracts the armature, causing the friction plates on the driving and driven sides to fit tightly together, transmitting power through friction. When the power is de-energized, the electromagnetic force disappears, and a spring or other reset device returns the armature to its original position, separating the friction plates and interrupting power transmission. Electromagnetic clutches offer high control precision; the magnetic force can be adjusted by the current to achieve smooth control of the engagement process. They also have a fast response time, facilitating automated control and enabling frequent engagement and disengagement operations. Furthermore, the installation layout of an electromagnetic clutch is flexible, eliminating the need for complex mechanical transmission structures.

[0102] Specifically, the electromagnetic clutch is equipped with a switch. When the switch is in the open state, the coil is energized, and the electromagnetic clutch can transmit force. When the switch is in the closed state, the coil is de-energized, the electromagnetic clutch disengages, and the force transmission is interrupted. When the lawnmower 1000 falls, the sensor detects the fall, and the control module of the lawnmower 1000 controls the switch of the electromagnetic clutch to close, thereby interrupting the force transmission.

[0103] In some embodiments, the type of clutch 20 can be flexibly selected based on the energy supply, cost budget, and automation requirements of the drive system 100. For scenarios without external power supply and where low cost and simplified structure are desired (such as small manual equipment and low-power transportation tools), a mechanical clutch can be preferred. Mechanical clutches do not require an electronic control module, have a more compact structure, lower cost, and can adapt to complex environments such as dust and vibration.

[0104] For scenarios requiring automated control and precise clutch switching (such as intelligent robots and electric construction machinery), electromagnetic clutches are the preferred choice. Electromagnetic clutches can be remotely controlled and respond quickly through an electronic control system.

[0105] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0106] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0107] The embodiments of this 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 this application should be included within the protection scope of this application.

Claims

1. A drive system, characterized in that, include: Electric motor; The clutch includes at least one first gear and a second gear, which mesh in a direction perpendicular to the ground or in a direction parallel to the ground; A movable wheel, including a steering shaft, the steering shaft being connected to the clutch; The clutch is disposed between the motor and the steering shaft; wherein the clutch has a first state and a second state, in the first state, the power of the motor can be transmitted to the steering shaft; in the second state, the clutch disconnects the power transmission between the motor and the steering shaft.

2. The drive system as described in claim 1, characterized in that, In the second state, the clutch engages in a direction perpendicular to the ground.

3. The drive system as described in claim 1 or 2, characterized in that, The first gear is fixedly sleeved on a rotating shaft; the second gear is sleeved on the rotating shaft, and the second gear can move relative to the rotating shaft; The first gear meshes with the second gear, and the meshing force exerted by the tooth surface of the first gear on the teeth of the second gear includes a component perpendicular to the ground. When the component is greater than a preset value, the clutch is in a second state; when the component is less than the preset value, the clutch is in a first state. In the first state, the first gear and the second gear remain relatively stationary in the vertical direction. In the second state, the second gear is displaced relative to the first gear in a direction perpendicular to the ground.

4. The drive system as described in claim 3, characterized in that, The clutch also includes: An elastic element is located on the side of the second gear away from the first gear. The first end of the elastic element is fixedly connected to the rotating shaft, and the second end abuts against the second gear. The preset value is the magnitude of the torque generated by the elastic element.

5. The drive system as described in claim 4, characterized in that, The torque generated by the elastic element is in the range of 2-20 N / M.

6. The drive system as described in claim 1, characterized in that, The drive system further includes at least one transmission gear disposed between the clutch and the moving wheel; and / or, the transmission gear is disposed between the motor and the clutch.

7. The drive system according to claim 6, characterized in that, The transmission gear is connected to the output shaft of the motor, and the transmission gear meshes with the first gear; and / or, the transmission gear is connected to the steering shaft, and the transmission gear meshes with the second gear.

8. The drive system as described in claim 1 or 2, characterized in that, The pitch circle diameter of the first gear is smaller than that of the second gear.

9. The drive system as described in claim 4, characterized in that, The clutch also includes: A fixed base is fixedly disposed on the rotating shaft, and the fixed base is fixedly connected to the first end of the elastic member.

10. A lawnmower, characterized in that, The lawnmower includes a housing, the bottom of which is provided with a working mechanism for performing cutting tasks; the lawnmower also includes a drive system as described in any one of claims 1-9, the drive system being disposed within the housing and driving the moving wheels on both sides of the housing to steer.

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