Coaxial different-rotation mowing robot cutting knife assembly
By using a coaxial rotating blade assembly for the lawn mowing robot, which utilizes counter-rotating blades and O-belt drive, the problems of missed cuts and tangential eddies in traditional lawn mowing robots are solved, achieving efficient and stable mowing results and handling of fine grass clippings.
Patent Information
- Application Number
- CN202511844384.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-09
- Publication Date
- 2026-02-03
AI Technical Summary
Traditional lawnmowers have problems such as missed cuts, large grass clippings, low efficiency and time consumption. In addition, the coaxial directional dual-blade mode generates tangential vortices, which leads to unstable low-speed operation.
The lawnmower robot uses a coaxial, opposite-rotation blade assembly. Two blades are mounted on the same shaft and rotate at high speed in opposite directions at a specified angle to form fine grass clippings. An O-belt is used to achieve coaxial, opposite-rotation transmission, offset torque, eliminate tangential eddies, and prevent slippage.
It improves mowing efficiency, reduces amplitude and noise, enhances the robot's operability and stability at low speeds, reduces missed mowing, and makes grass clippings more easily degraded by soil microorganisms.
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Figure CN121444718A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of agricultural robots, in particular to a coaxial and opposite rotation type mower robot cutter assembly. BACKGROUND
[0002] With the improvement of the level of agricultural mechanization, agricultural robots play an increasingly important role in agricultural operations. As a kind of agricultural robot, the cutter device of the mower robot has an important influence on the mowing efficiency and performance. The traditional mower robot usually adopts a cutter with rotating blades for cutting weeds. Most of the existing cutter devices on the market are single-shaft single-blade or double-shaft double-blade mode. This type of cutter needs to be adjusted in height to cut weeds from high to low, and has the disadvantages of missing cutting, large cutting grass clippings, low efficiency and time-consuming. The same coaxial directional double-blade on the market rotates in the same direction and generates a large tangential vortex. The tangential vortex cannot be eliminated, which causes instability in low-speed operation. SUMMARY
[0003] The purpose of the present application is to overcome the problems existing in the prior art, provide a coaxial and opposite rotation type mower robot cutter assembly, realize coaxial and opposite rotation transmission to improve mowing efficiency, and form small grass clippings to improve the cleaning effect. The coaxial and opposite rotation type cutter device adopts a structure in which two blades are installed on the same shaft to rotate in opposite directions at a specified angle. The upper and lower cutter rotation directions are opposite to realize torque cancellation of the two blade groups, eliminate the influence of tangential vortex on robot operation, and realize dynamic balance during high-speed operation. The o-shaped belt realizes coaxial and opposite rotation transmission of the two blades. When the blade hits a hard object, compared with the gear meshing type transmission, it can maintain transmission without immediate disengagement to prevent slipping.
[0004] To achieve the above technical purposes and effects, the present application realizes the following technical scheme: A coaxial and opposite rotation type mower robot cutter assembly, comprising a driving assembly and a cutter assembly driven by the driving assembly through a transmission assembly, the transmission assembly comprising a first driving pulley and a second driving pulley with the same rotation axis, a first driven pulley and a second driven pulley, the rotation axis of the first driving pulley and the first driven pulley being perpendicular, the rotation axis of the first driving pulley being connected to the rotation output end of the driving assembly, the first driving pulley being provided with an o-shaped belt and being wound back to the second driving pulley after crossing the first driven pulley and the second driven pulley, forming a belt transmission, so that the rotation directions of the first driving pulley and the second driving pulley are opposite, the first driving pulley or its rotation shaft connecting and driving a group of cutter assemblies as primary cutters, the second driving pulley or its rotation shaft connecting and driving another group of cutter assemblies as secondary cutters, so that the rotation directions of the cutters in the two groups of cutter assemblies are opposite and the torques are cancelled to form dynamic balance.
[0005] Further, the transmission assembly further comprises a drive shaft and a transmission shaft, one end of the drive shaft is connected to the output end of the driving assembly, the first driving pulley is fixed on the drive shaft and rotates with the drive shaft, the second driving pulley is rotatably arranged on the drive shaft through a corresponding bearing and does not rotate with the drive shaft, and the first driven pulley and the second driven pulley are arranged on the transmission shaft, and at least one of them does not rotate with the transmission shaft through a corresponding bearing.
[0006] Further, the cutter assembly comprises a cutter handle, the cutter handle is connected to the drive shaft or the second driving pulley and rotates with the corresponding connected object, and the cutter handle is connected with cutter pads at both ends, and corresponding flail cutters are arranged on the cutter pads.
[0007] Further, the cutter assembly as the primary cutter is arranged and installed in a cross shape with the cutter assembly as the secondary cutter, so as to reduce the influence of tangential vortex.
[0008] Further, the driving assembly comprises an engine, the output end of the engine is connected to the drive shaft, the engine is fixed on the engine support, the engine support is fixed on the cutter disc body, the exhaust pipe of the engine is fixed to the cutter disc body through an exhaust pipe fixing seat, and an oil tank is fixed on one side of the cutter disc body and used for supplying oil to the engine.
[0009] Further, a sleeve is rotatably connected to the drive shaft through a corresponding bearing, one end of the sleeve is fixed with a sleeve fixing seat, and the other end of the sleeve fixing seat is fixed on the cutter disc body.
[0010] The beneficial effects of the present application are: 1. The opposite rotating cutters of the present application can eliminate tangential vortex, offset the torque causing the lateral roll of the mower, and make the mower have better operability at low speed. Through experiments, it is known that the coaxial and different rotating cutters can reduce the overall amplitude of the mower by 67.5%, and reduce the noise decibel by 17.6%, so that the dynamic balance in the movement process is achieved.
[0011] 2. The coaxial and different rotating transmission structure of the present application uses an o-shaped belt, the o-shaped belt itself has a certain elasticity, can buffer the impact of hard objects, can produce a certain deformation and displacement, can maintain transmission without immediate disengagement, can prevent slipping, the contact surface of the o-shaped belt is very wide, the impact of hard object impact can be dispersed to the entire surface, the single-point stress is reduced, and the o-shaped belt is not easy to disengage, compared with a gear, the cost is lower, and the o-shaped belt is more easily applied.
[0012] 3. The coaxial and different rotating cutters of the present application can cut weeds at different angles repeatedly, are more thorough than ordinary cutters rotating in parallel, can polish weeds into more fine fragments, the area of the fine fragments is expanded, the fine fragments are more easily degraded and utilized by soil microorganisms, and the seeds of the weeds can be effectively damaged and inhibited from germination and regeneration.
[0013] 4. This invention features dual blades that rotate simultaneously for efficient operation, covering a larger area than a single blade. It can thoroughly trim the roots and stems of weeds in a single pass, making it difficult to leave any stumps and preventing weeds from being missed. A single blade is less effective at handling complex weeds. Attached Figure Description
[0014] Figure 1 This is a general diagram of the coaxial rotating cutter device of the present invention; Figure 2 This is a diagram of the driving component of the present invention; Figure 3 This is a general diagram of the coaxial rotating cutter assembly of the present invention; Figure 4 This is a cross-sectional view of the coaxial rotating cutter assembly of the present invention; Figure 5 This is a diagram of the cutting tool execution component of the present invention; Figure 6 This is a diagram of the coaxial rotating power transmission of the present invention; Figure 7 This is a comparison diagram of the amplitude of the present invention.
[0015] The following are the labeling instructions in the diagram: 1. Drive assembly, 2. Transmission assembly, 3. Cutter actuation assembly, 4. Engine, 5. Exhaust pipe, 6. Exhaust pipe mounting bracket, 7. Engine support, 8. Oil tank, 9. Cutter head body, 10. Upper drive pulley, 11. O-belt, 12. Upper driven pulley, 13. Left T-bearing housing, 14. Right T-bearing housing, 15. Snap ring, 16. Driven shaft, 17. Lower driven pulley, 18. Lower drive pulley, 19. Sleeve, 20. Roller bearing, 21. Sleeve mounting bracket, 22. Cutter mounting bracket, 23. Cutter handle, 24. Throwing cutter, 25. Cutter pad, 26. Drive shaft. Detailed Implementation
[0016] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0017] like Figure 1 , Figure 3 and Figure 6 As shown, a coaxial, non-rotating lawnmower robot blade assembly includes a drive assembly 1 and a blade assembly 3 driven by the drive assembly 1 through a transmission assembly 2. The transmission assembly 2 includes a first driving pulley 10 and a second driving pulley 18, and a first driven pulley 12 and a second driven pulley 17, all on the same rotation axis. The rotation axes of the first driving pulley 10 and the first driven pulley 12 are perpendicular to each other. Figure 4As shown, during actual installation, the relative distance between the centerlines of the grooves of the two driven pulleys needs to be equal to the distance between the centerlines of the grooves of the two driving pulleys. This is to maintain the coaxiality and balance of the transmission system. Coaxiality refers to the positional relationship between the two axes in space, ensuring they remain consistent. Figure 4 In this configuration, l1 and l2 are equal. The rotating shaft of the first driving pulley 10 is connected to the rotating output end of the drive assembly 1. The first driving pulley 10 is provided with an O-belt 11, which passes over the first driven pulley 12 and the second driven pulley 17 and then winds back onto the second driving pulley 18 to form a belt drive. Specifically, as shown... Figure 3 and Figure 6 As shown, during the winding process, the O-belt 11 starts from the first driving pulley 10, and both belts simultaneously hang down from above the first driven pulley 12 and the second driven pulley 17. Then, they fold back from below the first driven pulley 12 and the second driven pulley 17 and are looped onto the second driving pulley 18. If the centerline distances of the two belt grooves are not equal, the axes between the transmission elements will not be on the same straight line, potentially causing offset and imbalance. This needs to be addressed according to the above... Figure 4 The method described above avoids this situation, ultimately causing the first drive pulley 10 and the second drive pulley 18 to rotate in opposite directions. This belt drive method can also buffer the impact of hard objects and prevent slippage. The first drive pulley 10 or its shaft is connected to and drives a set of cutter assemblies 3 that serve as the main cutter, and the second drive pulley 18 or its shaft is connected to and drives another set of cutter assemblies 3 that serve as the secondary cutter. This causes the cutters in the two sets of cutter assemblies 3 to rotate in opposite directions, and the torque cancels out to form a dynamic balance.
[0018] The transmission assembly 2 further includes a drive shaft 26 and a transmission shaft 16. One end of the drive shaft 26 is connected to the output end of the drive assembly 1. The first driving pulley 10 is fixed on the drive shaft 26 and rotates with it. The second driving pulley 18 is rotatably mounted on the drive shaft 26 through a corresponding bearing and does not rotate with it. The first driven pulley 12 and the second driven pulley 17 are mounted on the transmission shaft 16, and at least one of them does not rotate with the transmission shaft 16 through a corresponding bearing. The two ends of the transmission shaft 16 are rotatably mounted on the first T-shaped bearing seat 13 and the second T-shaped bearing seat 14, respectively. The first T-shaped bearing seat 13 and the second T-shaped bearing seat 14 are fixed on the cutter head body 9.
[0019] like Figure 5As shown, the cutting blade assembly 3 includes a handle 23, which is a sheet metal part with a thickness of 5mm and a bending angle of 165°, which can improve the rigidity of the handle 23. The handle 23 is connected to the drive shaft 26 or the second drive pulley 18 and rotates together with the corresponding connected object. In this embodiment, the handle 23, which is the main cutting blade, is fixedly connected to the drive shaft 26 through the cutting blade fixing seat 22 and rotates. The handle 23, which is the secondary cutting blade, is directly fixedly connected to the second drive pulley 18 and rotates. Both ends of the handle 23 are respectively connected to cutting blade pads 25. Corresponding swivel blades 24 are installed on the cutting blade pads 25. The blades of the two swivel blades 24 are installed in positive and negative directions. The installation of positive and negative blades can achieve more uniform cutting.
[0020] The main cutter assembly 3 and the secondary cutter assembly 3 are installed in a cross-shaped configuration. The cross-shaped installation can achieve more uniform cutting because the blades of the main cutter and the secondary cutter are relatively dispersed, which can more fully cover the entire cutting area. It also helps to reduce the influence of tangential vortices and counteract the torque that causes the lawnmower to roll, making the lawnmower more maneuverable at low speeds.
[0021] like Figure 2 As shown, the drive assembly 1 includes an engine 4, the output end of which is connected to a drive shaft 26. The engine 4 is fixed to an engine support 4, which is fixed to the cutter head body 9. The engine support 4 elevates the engine 4, leaving space for the installation of corresponding pulleys. It also ensures that the overall installation position of the engine 4 is located at the center of the cutter head body 9. This balances the weight distribution, reduces the overall center offset of the robot, and reduces the transmission of vibration and shock from the engine 4 to the robot structure. The exhaust pipe 5 of the engine 4 is fixed to the cutter head body 9 through an exhaust pipe fixing seat 6 to discharge the exhaust gas produced after combustion and also to reduce noise. An oil tank 8 is fixed on one side of the cutter head body 9 for supplying oil to the engine.
[0022] A sleeve 19 is rotatably connected to the drive shaft 26 via corresponding bearings. Each bearing can be a roller bearing 20. One end of a sleeve fixing seat 21 is fixed to the sleeve 19, and the other end of the sleeve fixing seat 21 is fixed to the cutter head body 9. In this embodiment, the sleeve fixing seat 21 is designed as a Z-shape, and the inner corners are all reinforced with diagonal bracing to improve the strength of the parts.
[0023] Usage and working principle of this invention Whether in uneven terrain or densely weeded areas, it is essential to ensure that the cutting device operates effectively on uneven terrain. The coaxial, non-rotating cutting device of this invention provides better maneuverability and stability, adapting to rugged terrain. Figure 6As shown, the overall motion flow of the coaxial rotating cutter device is as follows: After the engine 4 is started, the engine 4 drives the first drive pulley 10 to rotate via the drive shaft 26. Taking clockwise as an example, the O-belt 11 is a transmission belt with a circular cross-section, which is tightly attached to the first drive pulley 10. When the first drive pulley 10 rotates, the O-belt 11 will also rotate, transmitting the power of the engine 4. At this time, the upper part of the O-belt 11 rotates in the positive direction, and the O-belt 11 then transmits the power to the first driven pulley 12 and... After the second driven pulley 17 rotates, the lower part of the O-belt 11 rotates in the opposite direction, transmitting power to the second driving pulley 18. At this time, the second driving pulley 18 rotates counterclockwise. The second driving pulley 18 drives the cutter assembly 3, which serves as the secondary cutter, mounted on it to move counterclockwise. At the same time, the cutter fixing seat 22, mounted at the bottom of the drive shaft 26, drives the cutter assembly 3, which serves as the primary cutter, to rotate clockwise with the drive shaft 26. This completes the movement process of the coaxial, opposite-rotation cutter. Through this movement process of the coaxial, opposite-rotation cutter device, it can effectively adapt to different agricultural scenarios, improve mowing efficiency, reduce missed cuts, and increase the stability of the robot. It is particularly suitable for agricultural operations in rugged terrain and dense vegetation environments.
[0024] To further verify the dynamic balance and other related performance of the coaxial rotating cutter device of this invention, a comparative verification was conducted with a single-axis, single-cutter device, focusing on two intuitive indicators: vehicle body vibration amplitude and noise. First, a vibration sensor mounted on the vehicle body was used to measure the vibration amplitude of the cutter during high-speed rotation. While ensuring the engine's fourth output shaft speed was 1500 rpm, both types of cutters were tested 30 times each. Figure 7 As shown, the average amplitude of the coaxial rotating cutter is approximately 1.15 cm, while the average amplitude of the single-axis single-blade cutter is approximately 3.54 cm, representing a 67.5% reduction in amplitude. Furthermore, the amplitude graph shows that the single-axis single-blade cutter exhibits greater amplitude fluctuations with peaks and troughs compared to the coaxial rotating cutter, indicating that the lawnmower robot achieves better dynamic balance at high speeds when using the coaxial rotating cutter compared to the single-axis single-blade mode. Noise levels were measured using a sound pressure level meter in both modes. The single-axis single-blade mode produced an average noise level of approximately 85 decibels, while the coaxial rotating cutter produced an average noise level of approximately 70 decibels, a decrease of 15 decibels, or 17.6%. This indicates that the tangential velocities of the coaxial rotating cutters cancel each other out during relative motion, thus reducing or eliminating tangential eddies. Tangential eddies are a type of mechanical vibration that can cause noise, and coaxial rotating cutters effectively reduce this vibration.
[0025] Furthermore, it should be noted that, unless otherwise specified or indicated, the terms "first," "second," etc., in the specification are used only to distinguish the various components, elements, steps, etc. in the specification, and are not used to indicate the logical or sequential relationships between the various components, elements, steps, etc.
[0026] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A coaxial rotating lawnmower robot blade assembly, comprising a drive assembly (1) and a blade assembly (3) driven by the drive assembly (1) through a transmission assembly (2), characterized in that, The transmission assembly (2) includes a first driving pulley (10) and a second driving pulley (18) on the same rotation axis, a first driven pulley (12) and a second driven pulley (17). The rotation axes of the first driving pulley (10) and the first driven pulley (12) are perpendicular. The rotation axis of the first driving pulley (10) is connected to the rotation output end of the drive assembly (1). The first driving pulley (10) is provided with an O-belt (11) that crosses the first driven pulley (12) and the second driven pulley (17). The drive pulley (17) then wraps around to the second drive pulley (18) to form a belt drive, so that the first drive pulley (10) and the second drive pulley (18) rotate in opposite directions. The first drive pulley (10) or its shaft is connected to and drives a set of cutter assemblies (3) as main cutters. The second drive pulley (18) or its shaft is connected to and drives another set of cutter assemblies (3) as secondary cutters, so that the cutters in the two sets of cutter assemblies (3) rotate in opposite directions and the torque cancels out to form a dynamic balance.
2. The coaxial rotating lawnmower robot blade assembly according to claim 1, characterized in that, The transmission assembly (2) further includes a drive shaft (26) and a transmission shaft (16). One end of the drive shaft (26) is connected to the output end of the drive assembly (1). The first drive pulley (10) is fixed on the drive shaft (26) and rotates with it. The second drive pulley (18) is rotatably mounted on the drive shaft (26) through a corresponding bearing and does not rotate with it. The first driven pulley (12) and the second driven pulley (17) are mounted on the transmission shaft (16), and at least one of them does not rotate with the transmission shaft (16) through a corresponding bearing.
3. The coaxial rotating lawnmower robot blade assembly according to claim 2, characterized in that, The cutter assembly (3) includes a handle (23), which is connected to a drive shaft (26) or a second drive pulley (18) and rotates with the corresponding connected object. Both ends of the handle (23) are connected to cutter pads (25), and corresponding sling cutters (24) are installed on the cutter pads (25).
4. The coaxial rotating lawnmower robot blade assembly according to claim 3, characterized in that, The cutter assembly (3), which serves as the main cutter, and the cutter assembly (3), which serves as the secondary cutter, are installed in a cross-shaped arrangement to reduce the influence of tangential eddies.
5. The coaxial rotating lawnmower robot blade assembly according to claim 2, characterized in that, The drive assembly (1) includes an engine (4), the output end of which is connected to a drive shaft (26). The engine (4) is fixed to an engine support (4), which is fixed to a cutter head body (9). The exhaust pipe (5) of the engine (4) is fixed to the cutter head body (9) via an exhaust pipe fixing seat (6). An oil tank (8) is fixed on one side of the cutter head body (9) for supplying oil to the engine.
6. The coaxial rotating lawnmower robot blade assembly according to claim 5, characterized in that, A sleeve (19) is rotatably connected to the drive shaft (26) via a corresponding bearing. One end of the sleeve fixing seat (21) is fixed to the sleeve (19), and the other end of the sleeve fixing seat (21) is fixed to the cutter head body (9).